Benchmarks Estimator
Sub Trajectory: Numerosity Estimation

Counts a portion of the to-be-estimated collection and uses that as a benchmark from which an estimate is made, intuitively or using repeated addition or multiplication. Scanning can be linked to recalled benchmarks.


You may see this:

Linked Image to Sign In/Sign Up page

Other Examples:

  • Shown 11, a child says "It looked closer to 10 than 20, so I guess 12."
  • Shown 45 objects spread out for 1 second and asked, "How many?," a child responds, "About 5 tens - Fifty."

Help your student become a(n) Benchmarks Estimator

Activities ask children to make reasonable estimation of the number of objects in a set, helping them form benchmarks (what would 10 of these look like? 100?) to guide their estimates (So,  How many in this jar then?)

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.