Students' difficulties in algebra are generally caused by the use of algebraic notation, the meaning of letters, as well as the types of relationships or methods used. Therefore, interpreting letters in algebra is one of the critical points in the transition from arithmetic to algebra. However, many students have misconceptions in interpreting…

The two studies reported on in this paper examine the features of words that distinguish students' performances on vocabulary assessments as a means of understanding what contributes to the ease or difficulty of vocabulary knowledge. The two studies differ in the type of assessment, the types of words that were studied, and the grade levels and…