Conceptually based instruction on place value and two-digit addition and subtraction without regrouping was provided in four first-grade classrooms, and more conventional textbook-based instruction ...

Students go over addition and subtraction with regrouping using different strategies.

A learning/teaching approach used base-ten blocks to embody the English named-value system of number words and digit cards to embody the positional base-ten system of numeration. Steps in addition and ...

Addition & subtraction with regrouping using different strategies to solve.