Composer to 20+; Composer Using Tens and Ones

Understands two-digit numbers as tens and ones; count with dimes and pennies; two-digit addition with regrouping.

Note: The goal for this level goes beyond simply memorizing math facts. The goal is knowing the “breakaparts,” which means the paired values that compose a target number. For example, the breakaparts for the target 4 are: 0 and 4, 1 and 3, 2 and 2. Knowing breakaparts means knowing the component parts in any order. In other words, knowing that 2 and 3 or 3 and 2 are breakaparts for the target 5. Frequently developed fluent combinations at this level include doubles, first 6 and 6 for the target 12, then 7 and 7 for the target 14, 8 and 8 for the target 16, and 9 and 9 for the target 18. Also common are near doubles combination close to 10, such as 5 and 6 for the target 11. Finally are combinations in which 3 and 4 are the smaller parts of targets 11 and 12, such as 3 and 8 for the target 11 or 4 and 8 for the target 12.


You may see this:

Linked Image to Sign In/Sign Up page

Other Examples:

  • "17 and 36 is like 17 and 3, which is 20, and 33, which is 53."

Help your student become a(n) Composer to 20+; Composer Using Tens and Ones

Activities ensure children are combining tens and ones meaningfully, understanding the different units, combining them separately and translating (renaming) between tens and ones.

Hiding Cubes

Make the Sum

Go Round

Chilly Cherry

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.