This study investigated whether the formation of equivalence classes among four types of addition problems increases the percentage of correct responses in problems with different forms of presentation, unknown positions and semantic structures. Eight 2nd to 5th grade Elementary School students with low percentages of correct responses in solving addition and subtraction problems participated in this study. After the formation of equivalence classes, an increase of correct responses in all problem types was observed. Then, the effect of teaching algorithms on solving addition and subtraction problems was investigated. No homogeneous pattern of improvement was observed after teaching these algorithms. Participants committed no errors on the generalization test. The results indicate that the adopted procedures contributed to improve the effectiveness of problem solving behavior.
problem solving; addition and subtraction; stimulus equivalence; teaching of algorithms
