Students' Concepts in Understanding Of Sound
  The article describes alternative concepts in understanding of sound observed among students at the elementary, high school and college level. The research confirmed some previously found alternative concepts and pointed to several others. A majority of the difficulties were found to be common to all levels. Also the percentage of students, who express alternative concepts, is nearly the same at all educational levels. However the percentage of students who clearly don't have alternative concepts, in general increases with educational level.   One set of observed difficulties, as a whole, compose conceptually structured and coherent, but naive picture on propagation of sound. Data were collected through written open-ended test questions on sample of 287 pupils and students in Split, Croatia 1997. 
Zdeslav Hrepic
physics.ed-ph