Effects of instructional Design Variables on Vocabulary Acquisition of LD Students

Two computer-assisted instructional vocabulary programs were used to teach definitions of 50 words to 25 learning disabled high school students. These students were matched on pretest scores and then randomly assigned to one of two computer-assisted instructional programs. The major differences between the programs were (a) the size of the teaching sets and (b) the procedures for cumulative review. One program provided teaching and practice exercises on small sets of words and cumulative review exercises on words the students learned in the program. The other program provided exercises on a large set of 25 words at a time and no cumulative review. Students received computerassisted vocabulary instruction for a maximum of eleven 20-minute sessions. The major finding was that significantly more students who were taught with the small teaching set program reached mastery within 11 sessions than students in the comparison group. Students in both programs learned as much (as measured by the criterion-referenced test) and retained as much, as measured by the maintenance test. Yet one group learned the material more efficiently. No significant differences were demonstrated on two transfer measures, an oral test of word meanings and a passage comprehension test.