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Gender Stereotypes as Hidden Curriculum: A Case of Vietnamese English Textbooks

Gender equality and women empowerment have become a buzzword for development during the past decades with numerous national and international policies, including educational policies. However, gender equality is normally conceptualized in quantitative terms of education such as low disparity in access to education between boys and girls, while qualitative aspects of gender equality are still left uncontested, among which is gender stereotypes in hidden curriculum. Gender stereotypes as a social construct, once imbedded in education and educational materials, certainly intervene the gender socialization process of students. The paper attempts to investigate this issue by employing a mixed qualitative and quantitative content analysis of the illustrations in English textbooks for Upper-secondary students in Vietnam. The analysis reveals stereotypes reflected in three main areas: occupations, sports and pastimes, and life duties, all of which confirm social and cultural norms of Vietnamese society towards a woman.


INTRODUCTION
Gender equality and women empowerment have become a buzzword for development during the past decades with NGOs, IGOs and governments using this "fashionable concept" (Medel-Anovuevo & Bochynek, 1995, p. 7) to include as one of their goals in policy and strategy documents. One example is The Millennium Development Goals (MDGs) established following the Millennium Summit of the United Nations, in which Goal 3 is to 'Promote gender equality and empower women'. The target is eliminating gender disparity in primary and secondary education preferably by 2015, specifically to have more equal ratios of girls to boys in primary, secondary and tertiary education. However, it can be argued that gender equality does not simply lie in equal access to education or equal opportunities to the labour market. Worldwide studies show that gender imbalances in education remain significant obstructions to achieving gender equality (UNESCO IBE, 2011). The study, henceforth, would like to examine such mentioned imbalance, specifically gender stereotypes in textbooks, or in other words, how women and men are portrayed in education.
According to Bourdieu (2005, cited in Madureira, 2009), the macro-social level of analysis facilitates our perception of "the reproduction of a hierarchical structure of gender that expresses inequalities between men and women in different domains", for instance autonomy, prestige or social status (p. 145). Given the importance of textbooks in the Vietnamese society, though being just a part of the national written curriculum, textbooks can be seen as either vehicles for such reproduction of social representations like gender stereotypes or tools for gender equality promotion (Levtov, 2014).
Although gender stereotypes are traditionally examined in linguistical, verbal and textual materials, we chose to focus on the illustrations, meaning the pictures and drawings in the textbooks, and sought to answer the question of what gender stereotypes are embedded in the illustrations of English textbooks for Vietnamese Upper-secondary students. To examine this issue, a mixed qualitative and quantitative content analysis method will be employed to analyze the illustrations in the selected set of textbooks for Uppersecondary (grade 10-12) students, coupled with the findings from previous studies conducted on gender stereotypes in textbooks for Primary students and Lower-secondary students in Vietnam as analytical points to shed light on this issue in Vietnamese education.

Vietnamese cultural, political and educational context
In order to understand gender stereotypes in the Vietnamese education in general and in textbooks in particular, it is essential to have an overall picture of the cultural and political contexts in which the Vietnamese education system is located.
Due to historical influences, the cultural construction of Vietnamese women is seen to consist of two elements: Confucianism and Socialism (Schuler et al., 2006). The Vietnamese culture was colonized by Confucianism for over 1000 years under the rule of Chinese feudal regime and henceforth, Confucian values and practices became firmly rooted in Vietnamese people's lives, even after Vietnam declared its independence in A.D. 938, and have since then become code of conduct (Bui, 2004). Confucian's ideas shape the order and formation of different relations at all levels of the Vietnamese society. Within the scope of the paper, the focus is more on women and the "culture of patriarchal authority and hierarchy" (Duong, 2001, p. 209). Confucianism makes a clear separation between the public sphere around which men activities revolve and the private sphere which women are supposed to belong to. A woman in the Confucian ideology was obliged to the virtue of male supremacy, named The Three Obediences including obeying to the father as a daughter, to the husband as a wife, and to the eldest son as a mother (Schuler et al., 2006). A model woman should also possess The Four Virtues, including diligent work, attractive appearance, modest and polite speech, and exemplary morality (Bui, 2004). Despite ample historical and social changes, the crux of Confucian values about gender, patriarchal thinking and women image "have not disappeared from official discourse" (World Bank report, 2011, p. 21) and remain visible among Vietnamese people (Slavicek, 2012), particularly in rural areas and among ethnic minorities.
Due to the prolonged wars against colonialism and poverty after independence, feminism has never explicitly happened in Vietnam, "the conceptual and linguistic structure of the Vietnamese culture contains no framework for feminism as a doctrine" either (Duong, 2001, p. 194). Nevertheless, women movements and gender equality did exist, though attached more to nationalism, socialism and communalism (Nguyen, 2011;Duong, 2001). In other words, men and women were seen equally and both genders were oppressed by imperialism and capitalism. Women at the time were more involved in movements against such oppressional causes rather than inequality rooted from the patriarchal ideology. One example for this argument is the foundation of Vietnamese Women's Union in 1930 (Nguyen, 2011). Education around the feudal time was the privilege of only men and aristocrats (Nguyen & Nguyen, 2008).
After the wars against French and American colonization and invasion, progressive laws have been made to eradicate the gap between men and women in every aspect of life. For example, the Government, starting from the philosophy "an illiterate nation is a powerless one" after claiming its independence from colonialism in 1945, issued Decree No. 17-SL in which it was stated "Everyone in the country has to be literate", and henceforth literacy was officially a right of women as well (Nguyen & Nguyen, 2008). The General education since then consists of three levels: primary (for grade 1 to 5, children starting from six years old), lower secondary (grade 6 to 9) and upper secondary (grade 10 to 12).
Later under a striking renovation policy affecting both social and economic sectors in 1986 named Doi Moi, Vietnam initiated a vast program of legal reforms, among which were human rights and women's mobilization into the labour market (Duong, 2001). After that, more laws have been enacted to accelerate progress on gender equality, such as the law on Gender Equality in 2006, the law on Domestic Violence Prevention and Control in 2007, and National Strategy for Gender Equality for the 2011-2020 period signed on December 2012 by Government of Vietnam. All the optimistic successful statistics and policies give Vietnam 'a reputation throughout Asia for relative gender equality' and has been considered successful in 'being able to close gender gaps in education, access to health care, and many aspects of employment since the early 1990s' (World Bank, 2006. Despite all the progress so far made with relatively equal access to education between boys and girls in Vietnam (92.3% and 91.5% respectively for primary education, 80.1% and 82.6% respectively for Lower secondary education), gender equality still remains an issue in education (Dang et al., 2013, p. 50). The reason is that other educational factors and practices, including curriculum and textbooks, as well contribute to inequalities. In the National Strategy for Gender Equality for the 2011-2020 period signed on December 2012 (Objective 3), the solutions to this problem were proposed to incorporate more gender equality in the content of the national curricula and gender matters in policies and educational programs, and to eliminate messages and images bearing gender prejudice in the textbooks. This lights up a promising and optimistic future of public awareness of the issue. Simultaneously, it is worth a critical scrutiny of how genders are currently portrayed in the educational materials.

Gender socialization and Gender stereotypes
Gender is a social construct instead of "a biological given" or an achieved status since it must be acquired by learning rather than a prescribed nature that a person is born with (Bandura & Bussey, 1999, p. 683). The social construct refers to traits of social, cultural or psychological categories attached to males and females (Lindsey, 2016). According to Kretchmar (2009, p. 1), when the focus on gender entails questions to which "the answers remain elusive", gender socialization has become an emerging area of interest within sociology. As a consequence, increasing attention has been paid to gender socialization which is defined by Wharton (2005, cited in Kretchmar, 2009) as the "processes through which individuals take on gendered qualities and characteristics. . . and learn what their society expects of them as males or females" (p. 1). In each of us there are two beings coexisting: the individual being, and the social being. The latter refers to a system of beliefs, ideas, traditions and practices that are not inherent in our personality but belong to the group that we are part of (Durkheim, 1956;Biesta, 2010). Durkheim (1956) emphasizes that social being is constituted and completed by education. His thesis is partly reflected in Biesta's (2010) thesis of three functions of education, among which is socialization, meaning that through education, learners become part of "a particular social, cultural and political orders" (p. 20). Having said that, education has socializing effects on gender development; and gender socialization also happens through education. Viewed from the sociological perspective, the pattern of the abovementioned gendered social, cultural and psychological norms, meaning gender stereotypes, shape "styles of behaviours", lead to "gendered perception", frame "evaluation, and treatment of males and females" in selectively pre-determined ways and even "channel men and women into different life paths" (Bandura & Bussey, 1999, p. 683;UNESCO, 2013, p. 23;Marinova, 2003, p. 4). In other words, gender stereotypes intervene in the gender socialization process.
As emphasized in Bandura and Bussey (1999), the source of stereotypical gender differentiation lies in social and cultural practices. The concept of gender stereotypes has attracted attention of scholars and researchers for a long time. As Mkuchu (2004, cited in Seker & Dincer, 2014 demonstrates, it is the result of every culture's assigning "particular traits to the dynamic roles" attached to the gender identity of individuals (p. 91). Bohan (2011) proposes a similar definition, adding that gender stereotypes may restrain one's natural gifts and capabilities, or may become obstacles of life and educational opportunities. Other researchers like Golombok andFivush (1994, cited in Vu, 2008) or Gaur and Jain (2013) define the term as a set of popular beliefs that certain attitudes and behaviors are expected from males or females in a specific culture or society. Despite subtle nuances in defining the term, there is a general consensus that gender stereotypes subsume information not only physical and psychological traits, hobbies and interests, but social relations and occupations as well (Gaur & Jain, 2013). This is also how gender stereotypes are conceptualized in this paper.
In lieu of being planned or stated as a learning objective, gender stereotypes are implicit and hidden to teachers, students, "at least at a conscious level" (Print, 1993, p. 11). In other words, gender stereotypes are imbedded in the hidden curriculum of education systems, which refers to the non-explicit aspects of the curriculum, as defined by the Sociology of Education, to fulfill the socialization function of education (Print, 1993, Biesta, 2010, Hernandez et.al., 2013. Hidden curriculum, according to Hernandez et al. (2013), was first coined by Philip W. Jackson. It involves the learning of social norms, values, traditions, assumptions, which are often left uncontested or remain unarticulated (Print, 1993;Hernandez et al., 2013).

Gender stereotypes in textbooks: A hidden curriculum
Given the status of textbooks as "repositories of official knowledge" (Ferree & Hall, 1996, cited in Cassese & Bos, 2013, they dictate the content, the order as well as the way learners learn (McGrath, 2006). Textbooks, furthermore, do not simply play the role as neutral educational tools but "sterile delivery systems for predetermined set of facts" (Cassese & Bos, 2013, p. 214), keep social cohesion sustained and are considered being contributive to socialization and instrumental for social change (Brugeilles & Cromer, 2009). As the most visible manifestation of the curriculum, textbooks convey messages that shape attitudes, values, and behaviours. Henceforth, to acquire an insightful look into the curriculum, the textbooks are chosen as an important entry point of analysis of gender stereotypes.
There is a wide literature on gender stereotypes in textbooks worldwide. Cassese and Bos (2013) examine the content of 22 introductory-level political textbooks and the results reveal underrepresentation of women in political science, narrow "inclusion of content pertaining to women's behavior at both the mass and elite levels" and hence entails lower sense of political efficiency in female students (p. 221). Armini and Birjandi (2012, p. 135) conduct a review of the literature of the field, showing that gender stereotypes and gender bias exist in education materials. For instance, nouns which describe females' activities are seven times less than those of males, words that describe females are mostly passive in contrast with active words for males, or females are depicted mainly as housewives doing home-care work. A number of other studies on various English as Foreign/Second Language textbooks present consistent and prevalent male dominance and female traditional stereotypical roles, even though textbook writers do become more conscious about sexism (Armini & Birjandi, 2012). Similar situations are also detected in children's literature and story books (Vu, 2008).
In Vietnam, there are also studies on the same topic for different levels of education. Vu's study named Gender Stereotypes in Story Textbooks for Primary School Students in Vietnam (2008) aims to investigate the issue in story textbooks for students from grade 1 to 5. There exists the outnumbering of male characters, as well as the great discrepancy between females and males in terms of occupations, personalities and social status. Pictorial materials incorporated in English textbooks for Lower-secondary students (grade 6-9) presented in Nguyen's research (2013) named Evaluation of Illustrations in English textbooks for Lower Secondary Students in Vietnam also carry gender stereotypes in categories like occupations, family duties and sports and pastimes. In line with these two studies, this study examines whether a similar issue exists in the English textbooks' illustrations for Vietnamese Upper-secondary students and what specific stereotypes are in the hidden curriculum.

METHODOLOGY
The current study is based on a textbook analysis, particularly the focus will be on the illustrations of English textbooks for Vietnamese Upper-secondary students. English is a commonly used language by academics, international trade and communication. It became officially sanctioned as the working language of The Association of Southeast Asian Nations (ASEAN), a strategic regional organization in which Vietnam is a member since 1995 (Article 34, ASEAN Charter 2009, cited in Kirkpatrick, 2012. In 2008, The Prime Minister ratified the 2008-2020 Plan for the Teaching and Learning of Foreign Languages in the National Education System in which English is placed at the heart of the strategy for teaching and learning foreign languages (Nguyen, 2013). We, henceforth, selected English textbooks to examine due to its increasingly popular and important position in Vietnamese education and society.
All the textbooks chosen in this study are published by The Education Publishing House, the official publisher of Ministry of Education and Training (MOET). The content of the books must be approved by councils including a number of experienced teachers, educational managers and scientists of related areas (Article 8, Education Act, cited in Do, 2002Do, /2003. These textbooks are used nationwide targeting at students in Upper-secondary schools, aging from 15 to 18 years old, grade 10 to 12.
-  (2007), Hanoi: Education Publishing House) Since gender stereotypes are not a planned objective for students to achieve, we investigated the hidden curriculum in the chosen textbooks, embedded in the illustrations including pictures and drawings accompanying texts. Glache (2000, cited in Dominguez, 2003 states that the analysis of images is "poststructuralist analytical techniques in deconstructing universal truth" for "enlightenment" and for challenging the taken-for-grantedness. Illustrations are not only used for decorative purposes to support textual elements, they do convey meanings and messages themselves and "point to particular interpretations of experience and forms of social interaction" (Kress & van Leeuwen, 1996, cited in Nguyen, 2011. Qualitative content analysis method is employed as the primary approach for analysis in the current study, with an aim to "provide knowledge and understanding of the phenomenon under study" (Downe-Wamboldt, 1992, cited in Hsieh & Shannon, 2005, p. 1278). This method is cost effective, generates the researcher more freedom to work with available data. Nonetheless, the demerit of content analysis is that it is limited to examining already recorded messages, which means the analysis can be subjective and prone to the researcher's bias (Berg, 2007). Being aware of this disadvantage, we employed quantitative content analysis method in the way that message elements were enumerated to indicate the frequency of explicit themes and topics to avoid biased interpretation of the illustrations (Kondracki, 2002).

RESULTS AND DISCUSSION
The current research examines gender stereotypes in visual elements in the English textbooks for students in grade 10, 11 and 12. Visual images elicited as data for analysis only refer to photos and drawings, the former are believed to provide a sense of reality and authenticity while the latter have more flexibility and emphasis on details if necessary (Tomlinson & Masuhara, 2004, cited in Nguyen, 2013. The findings are presented into three big themes: gender stereotypes in occupations, in sports and pastimes, and in life duties.

Gender stereotypes in occupations
There are a variety of jobs and occupations depicted in the illustrations of the three books, which are briefly presented in table 1 below.  Table 1 that there is a significant difference in the number of men depicted with jobs and that of women (45 times and 30 times respectively). Men are depicted with more and varied choices of occupations and they dominate in certain occupational areas, such as in football or military areas while females are found mostly working as teachers or farmers. However, as stereotypes in sports as an occupation overlap with stereotypes in sports that females and males tend to play, it would be thoroughly elaborated in the later section.
The data yielded concurs with previous studies by Vu (2008) and Nguyen (2013) that the labour market is male-dominated. The results in Vu's study (2008) reveal a discrepancy in occupations between the two genders. Female characters in children's stories are more circumscribed in a significant limited range of occupations compared to male characters (Vu, 2008). Similarly in his research, Nguyen (2003) quantifies the gender imbalance in illustrations in the English textbooks for Lower-secondary students, which results in the total number of jobs that women do being just half of that done by men (11 and 22 jobs respectively) (p. 53). Besides, women in the investigated set of books are found to be tied with jobs that are assumed to need more patience or verbal capability, such as a market vendor or particularly a teacher (3 times). In fact, the report on gender and career prospects in contemporary Vietnamese society confirms what is illustrated in the textbooks. Over 60% of the total teachers in Vietnam in all levels are females (UNESCO, 2013). Furthermore, among the 15 year olds in Vietnam, the age of the targeted students of the currently examined books, most professions are divided according to personal and physical traits that are supposed to be more masculine or feminine. For example, professions in mechanics, construction and the police considered "heavy occupations" and involving more strength should suit better to men while jobs that are more "people oriented" or "delicate" such as teaching, tailoring or small trade are presumed to be done by women. (UNESCO, 2013, p. 32) Even though agreeing with the previous studies on the unequal presentation of jobs between women and men, a difference noted in the current paper is that these textbooks feature women in certain similar job categories with men, including politics or academic and scientific areas, rather than women being restrained with work revolving around their house. Female politicians, another example, though depicted three times in the books, are still outnumbered by men. However, Vietnamese women in particular are underrepresented. The only female scientist, for example, is a Polish physicist. Besides, Vietnamese women's participation in politics are not well presented. Among the three pictures with female politicians, one picture represents ten country leaders in the occasion of 13 th ASEAN summit with nine male politicians and one female, Indonesian Prime Minister. The other two illustrations are not Vietnamese women either. While in a report titled Vietnam Country Gender Assessment in 2006, the time before the books were published, the World Bank noted that representation of women in Vietnam's National Assembly "is high by regional standards" with approximately 30% of the seats were women (p. 67), this is not sufficiently reflected in the examined study materials.
The illustrations in the textbooks, in brief, reveal a disparity in the number of jobs as well as job choices between men and women, meaning that women are restrained with fewer jobs. Social norms and perceptions about masculinity and femininity, male strength and female delicateness, what occupation should be done by men or what is better done by women, can also be seen through the illustrations.

Gender stereotypes in sports and pastimes
The sports and activities for males and females in the books reveal certain patterns, implying that there are sports that are more associated with men while others with women. Table 2 presents the depiction of males and females regarding sports in the books.

Table 2 Presentation of sports and pastimes of males and females in English 10, 11, 12
Female Male Football, Gymnastics (2), Water polo, Swimming (3), Synchronized swimming (2) Football (2) (2) Fishing (3), Photography (2), Playing musical instruments (3), Dancing (2) Total: 4 activities/10 illustrations Total: 4 activities/ 10 illustrations The significant discrepancy between the number of sports that men and women play is clearly shown in the table (14 sports and 5 sports respectively). Four out of five sports which women are featured to play in the studied set of books are collective sports and require more dexterity like gymnastics or less muscular strength such as swimming or synchronized swimming. Females are also depicted with specific hobbies like playing musical instruments, watching a movie or chatting with each other. Meanwhile, males tend to have a more outdoor activity, such as taking photographs or going fishing. The similar results are found in English books for Lower-secondary students (Nguyen, 2013). According to Nguyen's (2013) study, while boys are depicted in sports 55 times in 14 different sports, girls get 27 illustrations in 10 sports which normally require more dexterity and less competitiveness. Besides, pastimes for females are portrayed as buying or making clothes or chatting over the phone while boys as watching TV or fishing and fixing household items. In terms of sports, men are portrayed to outnumber women. Besides, in all ten illustrations, none of the females featured doing sports is Vietnamese. It can be deduced that Vietnamese women again are barely presented in sport activities, which traditionally were not supposed to be for them. Being influenced by Chinese Confucianism, the model of a dignified and exemplary woman in Vietnamese traditional society was to be proficient in music (lute playing particularly), chess, calligraphy and poetry, and painting (translated as Cam Ky Thi Hoa) (Lockard, 2009;Nguyen, 2014). However, females nowadays have more freedom in choosing their pastime activities, including sports. Many Vietnamese women even choose sports as a professional career to pursue, however, there exist unequal social responses between women and men doing sports. Football and Vietnamese national women's football team are taken as a particular example. Despite efforts and successive regional trophies in recent years, in terms of public and media attention, incomes, and bonus, female footballers are not treated equally as their male counterparts. In the historic victory of Vietnam's national women's football team which marked first time advancement of women's football in The Asian Games (ASIAD) in late September 2014, there were only seven Vietnamese fans in the stands of the stadium to support the team while around 2,000 Vietnamese fans came to support Vietnamese men's national team (Tuoitrenews, 2014). The event later was named 'The lonely victory' by the media. The Vietnam Football Federation (VFF) decided to reward the team with 1 billion Vietnamese dong for their achievement. In contrast, although the national men football team was defeated in Asian Football Federation (AFF) Cup in early December 2014, a football championship of Southeast Asia of smaller scale compared with ASIAD, they were awarded over 5 billion Vietnamese dongs by VFF as announced in Bongda.com.vn, the online website under the authority of Vietnamese General Department of Sports and Physical Training. This situation does not just happen only in the Vietnamese society, however, such stereotypes in sports and pastimes which have effects on the socialization process of students need to be contested.

Gender stereotypes in life duties
In this set of books, women are featured mostly in domestic settings, such as in family parties, family reunions or marriage ceremonies. Women are found doing cooking, shopping for food, taking care of children or helping children with their homework. In English 11 (p. 160), the pictures tell a story of a group of students going camping. While the boys are swimming, taking photographs, there are some girls going and picking flowers and two are cooking together with one boy standing and watching. A picture in English 11 (p. 80) captures a glimpse of a common family life in many poor or rural areas in Vietnam with a stay-at-home mother feeding, raising up five or six children and doing household chores. Meanwhile, the father is the main labourer, normally doing farming work. Nguyen's analysis (2013) shares similar results. Women are depicted to be attached to family duties in a domestic setting or situation like the mother is cooking while her husband is reading a newspaper or the daughter is doing homework while the boys are playing football. However, unlike the previous study in which there is notably no presentation of men doing any housework, the current research shows there is less depiction of women doing housework or caregiving all by themselves. An example is a picture in English 12 (p. 12) in which the mother is standing next to her daughter who is studying, while her husband is playing with the little son rather than sitting and reading a newspaper as a drawing in Nguyen's study (2013).
Another major finding is that the image of Vietnamese women in the illustrations of this set of books reflects a modern stereotype. A typical example is the pictures in English 12, Unit 15 named Women in society (p. 162). The pictures feature a stereotypical modern Vietnamese wife and mother who after work hurries to shop for food, helping both her children with studying or homework, taking care of the children after dinner and doing cleaning like throwing trash. The similar story is in fact described in a written text in Unit 1, English 12 (p. 13), in which the mother works as a nurse with long hours in a big hospital and after a nigh shift but still is the one "running the household", the first one to get up to prepare breakfast for every family member or the one who "rushes to the market then hurries home so that dinner is ready on the table by the time Dad gets home".
Given the long history under feudalism and patriarchal ideologies, all the statistics and policies do present an optimistic picture of gender equality and women empowerment in Vietnam. Yet, men are more often selected for advanced training opportunities or promotions involving more power and decisionmaking, and women continue to "shoulder the majority of unremunerated housework and care-work despite contributing equal time to income-generating work" (Kelly, 2011, p. 5). This phenomenon reflects the reality of Vietnamese women in the contemporary society. As specified in Kelly (2011), "neo-traditional discourse positions women as care givers within Vietnamese society" (p. 5). Although the government acknowledges women's dedication to home making through awards and certificates such as Vietnamese women: good at national tasks and good at housework, there is little encouragement for Vietnamese men who are contributive to both tasks. In other words, little has been done to loosen the constraints on women by traditional norms but instead the burden that modern Vietnamese women have to shoulder has been doubled since the society expects them to fulfill the tasks both in domestic and public spheres (Nguyen, 2011).
This presentation of life duties well reflects the reality in the contemporary Vietnamese society and what the society expects from women. Being integrated implicitly in educational materials such as textbooks, the stereotypes confirm the regarded standard social norms and values and navigate how a woman should lead her life in Vietnamese society.

CONCLUSION
This study examines gender stereotypes as hidden curriculum embedded in the illustrations of English textbooks for Vietnamese Upper-secondary students. On the grounds of Durkheim's (1956) and Biesta's (2010) thesis on education and its function of socialization, we approached gender stereotypes as a social construct. We followed the argument that since gender stereotypes are hidden in curriculum, they will intervene students' gender socialization by shaping their mindset of what the society expects from their masculinity or femininity. Being the strong manifestation of curriculum, textbooks were chosen as the empirical data. The set of textbooks are English 10, English 11 and English 12, which are used nationwide in Vietnam. A mix of quantitative and qualitative content analysis study was conducted with the aim to analyze what gender stereotypes are incorporated in visual elements in the textbooks. From what the data presents, gender stereotypes could be seen in occupations, sports and hobbies, and life duties.
It must be noted that the status of Vietnamese women is no longer that being oppressed since Vietnamese first contact with Western culture, France specifically, in the middle of the 19 th century (Nguyen, 2011). A remarkable example is the rising number of women in leadership and political positions and the increasingly narrow gap between the number of girls and boys having access to secondary education (Dang et al., 2013, p. 49). However, gender equality is not just about quantitative aspect, but also about qualitative, which refers to social evaluation and treatment to men and women and the way women and men think they should be to reach social expectations.
Data emerging from the data revealed an imbalance between the number of job depictions between men and women and the underrepresentation of Vietnamese women particularly in professions which are seen as high status such as scientist and politician. Males are featured to have a variety of occupational choices, ranging from jobs involving more muscular strength (firemen, bodyguard, police officer) to jobs more requiring talents (singer, writer, music composer). In contrast, females tend to have fewer options. They are often portrayed as students or working in the teaching or farming sectors. Studies into the occupational aspirations of students have found that their career choice is under a significant influence of gcndcr stereotyping they encounter in their life, in which education is a major part (Purvis, 1987;UNESCO, 2013). When students learn such repetition of depiction in occupation, they have certain presumptions of what is more acceptable for men and for women to pursue as a career, which, as argued by Bandura and Bussey (1999) and Marinova (2003), directs men and women into different life choices.
The stereotypes were also found in sports and leisure activities that males and females take up. Men are found to be pictured with 14 different types of sports while women are in only 5 sports which are mostly gymnastics or swimming. Moreover, there is no illustration featuring Vietnamese women playing any sport, both professionally or as a hobby despite the fact that Vietnamese athletes and sports activities are gaining more and more popularity among Vietnamese citizen, including women. The traditional image of women with indoor activities like cooking, embroidery, playing musical instruments, singing and dancing is still more expected from society. This could be seen in the way girls are portrayed in illustrations of leisure activities. Men, instead, are seen with more outdoor leisure activities or playing different kinds of sports. As stated in a report by SDG IWP (2008), although sport is an indispensable part of almost every country, it is often disregarded as a means to promote gender equality because girls and women are not universally surmised as suitable for doing sport. "Existing social constructs of masculinity and femininity", or what a particular socio-cultural context attaches to a man or a woman, are the determinants of the access as well as the levels of participation that each individual may have (SDG IWP, 2008, p. 131.). The stereotypes found in the illustrations of the textbooks are factors to confirm such existing social constructs.
The last stereotype emerging from the data of the study was women's life duties. Vietnamese women, under a long history of Confucianism influence, are confined in a traditional image of taking care of the family, raising and feeding children, and sacrificing for their husbands. Rather than being independent, Vietnamese women are often found to be in a domestic setting with the whole family or their husbands. Otherwise, they are portrayed to be doing house chores such as running errands, cooking or taking care of children. A notable point in the study is the depiction of Vietnamese women in this set of books are not just conventional housewives but modern women who are also contributive to the financial condition of the whole family. However, their housework burden is not any less. This reflects the existing responsibilities of women in the contemporary Vietnamese society who are expected to be both proficient at work and social duties and at the same time take very good care of the whole family and family duties.
In conclusion, all the repeated above-mentioned stereotypes shape rigid mindset of students towards the stratification of what defines masculinity and femininity, which may be the starting point of social prejudice. In other words, they actually reinforce gender inequality in qualitative terms. As stereotypes are hidden in the curriculum, they can be acquired by students unknowingly and unconsciously and have certain influences on the gender socialization process of students. Hidden curriculum in gender, as argued by Hernandez et al. (2013, p. 90), are made out of "social constructions of thoughts" and will therefore be "a form of power" that "establishes, supports and permeates the concepts, values".
This study contributes to the area of gender equality in education and educational materials in particular by focusing on gender stereotypes as hidden curriculum depicted in the illustrations of the English textbooks for Upper-secondary students in Vietnam. It will hopefully offer an insight into the issue as well as suggestions for the textbooks revision process of policy makers in Vietnam.

ACKNOWLEDGEMENT
The corresponding author would like to thank Mr. Nguyen Thanh Van for his generosity in sharing his work with the author and for his pleasant talks and intellectual humour she had a chance to experience while being his colleague. The author would also want to thank Dr. Phung Ha Thanh from Vietnam National University for her encouragement, inspiration and her opinion when the first seeds of idea for this article were sowed. Last but not least, the authors are grateful to the anonymous reviewer for the comments on the initial submission of the article.