{'fraction_non_alphanumeric': 0.011217948717948718, 'fraction_numerical': 0.0016025641025641025, 'mean_word_length': 5.510416666666667, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Principal Leadership Long-Term Indirect Effects on Learning Growth in Mathematics

In both the school effectiveness and the educational administration literature, growing attention has been paid to the extent of principal leadership effects and the means by which they affect school performance. The main goal of this study is to estimate the effects of principal leadership on students' achievement growth in mathematics over a period of 6 years. Results from multilevel latent growth show that the impact of principal leadership on students' achievement growth is mediated by teacher collaboration and collective efficacy.