Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.
Subject Area: Mathematics
Grade: 1
Domain-Subdomain: Number and Operations in Base Ten
Cluster: Use place value understanding and properties of operations to add and subtract. (Major Cluster) -

Clusters should not be sorted from Major to Supporting and then taught in that order. To do so would strip the coherence of the mathematical ideas and miss the opportunity to enhance the major work of the grade with the supporting clusters.

Date Adopted or Revised: 02/14
Date of Last Rating: 02/14
Status: State Board Approved