Toy Shop: Deriver
Activity Type: Computer Activity
Deriver +/- (Composing Numbers) Deriver +/- (Adding/Subtracting)
Help the twins get the same number of toys. Choose the numeral that shows the number of toys one twin needs to give the other.Start Game
Special Thanks To
The research reported here was supported by the Institute of Education Sciences, U.S. Department of Education, through grant numbers R305K050157, R305A120813, R305A110188, and R305A150243. to the University of Denver. The opinions expressed are those of the authors and do not represent views of the Institute or the U.S. Department of Education.