Domain

Operations and Algebraic Thinking

Cluster

Add and subtract within 20

Standard(s)

NC.2.OA.2 - Demonstrate fluency with addition and subtraction, within 20, using mental strategies

Materials

None

Task

Teacher Notes:  1) The category “Basic Fact Automaticity” means the student answers within about 5 seconds.  2)  Student Problem Sheet may be looked at by the student or kept out of their sight.  3)  Teacher Recording Sheet is not to be seen by the student.

Ask the student to find a sum and explain how they calculated.

i.e. What is 9+4? How do you know?

This task is meant to be used in a 1-on-1 setting. Teacher may administer this task over a series of days.

Continuum of Understanding

Not Yet Proficient

Needs prerequisite concepts- using strategies to add and subtract within 20 to demonstrate fluency (counting on, making ten, decomposing leading number) NC.1.OA.6

●   Student is unable to accurately calculate sums.

●   Student may calculate sums correctly, but only uses a counting all strategy.

Checklist for teacher to identify mastery of standard:

❑    See Teacher Record Sheet

Progressing

●       Student is able to employ strategies including counting on, adding doubles (then +1 or +2), decomposing addends to create easier sums, or making ten.

●       Student shows some basic fact automaticity for more than half of the sums.

Meets Expectation

●     Student is able to employ strategies including counting on, adding doubles (then +1 or +2), decomposing addends to create easier sums, or making ten, and can explain their thinking.

●     Student shows basic fact automaticity for the sums.