Developing the concept of perimeter and area in students with learning disabilities (LD)

The present research is aimed at developing an educational program effective for the development of the concepts of perimeter and area in students with LD and testing this program. The study combined action research with quasi-experimental design involving experimental (LD) and comparison (non-LD) groups. The intervention program consisted of 12 sessions and included the development of both general cognitive strategies and more specific geometry strategies. The central element of the program was the elaboration of the concept of "measure" and its use for the estimation of length and area. The comparison of the experimental group pre-and post-program test results demonstrated statistically significant improvement of pupils' performance in all tasks. Students in the comparison (non-LD) group, predictably, started with better pre-test results. However, they made less impressive changes than their peers from the experimental (LD) group, who actually even outperformed the comparison group at the post-test. It is possible to conclude that an intervention program based on a combination of general cognitive strategies with the concept and operation of "measurement" appears to be effective in significantly improving the geometry task performance of pupils with LD and facilitating their inclusion into regular classrooms.