Report provides new data concerning children's accuracy as measured by previous studies and clarifies progress of first graders during entire year on difficult single-digit addition and subtraction problems. Discussion focuses on advantages of an adding on interpretation of subtraction and the importance of emphasizing conceptual understanding…

Compared use of derived fact strategies involving addition and subtraction by 20 learning-disabled students (LDSs) from an intermediate level self-contained class to 22 grade-3 normally achieving students (NASs). LDSs did not differ from NASs in verbal fluency or use of alternative strategies. (Contains 20 references.) (MDH)