Part-Whole +/-

Has an initial Part-Whole understanding and can solve all previous problem types using flexible strategies. May even use some known combinations, such as 5+5 is 10. Sometimes can do Start Unknown (e.g., _ + 6 = 11), but only by trial and error. 



You may see this:

Linked Image to Sign In/Sign Up page

Other Examples:

  • When asked, "You had some balls. Then you get 6 more. Now, you have 11 balls. How many did you start with?", lays out 6, then 3 more, counts and gets 9. Puts 1 more with the 3...says, "Ten," then puts 1 more. Counts up from 6 to 11, then re-counts the group added, and says, "Five!" (join, start unknown problem; counting up to strategy)
  • When asked, "You have 11 pencils and give 7 away. How many do you still have?", says, "Seven...eight, nine, ten, eleven," while putting up four fingers, and says, "Four!" (separate, result unknown problem; counting up to strategy)

Help your student become a(n) Part-Whole +/-

These activities challenge children to solve all the addition and subtraction problem types they have already learned to solve with more sophisticated strategies, including more use of finger patterns and even some well-known combinations (e.g., "3 and 3 is 6").

Break and Make
Break and Make
Roll Call
Roll Call

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.