Problem Solver +/- (CN)

Solves all types of problems, with flexible strategies and known combinations. Multidigit may be solved by incrementing or combining tens and ones.

Activities

You may see this:

Linked Image to Sign In/Sign Up page

Other Examples:

  • Asked, "If I have 13 and you have 9, how could we have the same number?", says, "9 and 1 is 10, then 3 more to make 13. 1 and 3 is 4. I need 4 more!"
  • Asked "What's 28 + 35?", incrementer thinks: "20 + 30 = 50; +8 = 58; 2 more is 60, 3 more is 63." Combining tens and ones: "20 + 30 = 50. 8 + 5 is like 8 plus 2 and 3 more, so, it's 13. 50 and 13 is 63."

Help your student become a(n) Problem Solver +/- (CN)

Activities present problems such as those that bridge decades,  77 + 3 and 25 + 7. As always, they use manipulatives and modeling as necessary, until children can solve the problems mentally, or with drawings such as the empty number line. When children can do this, hide those visual models so children build mental models.

Special Thanks To

Institute of Education Sciences
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.