CCSS.Math.Content.1.OA.C

CCSS.Math.Content.1.OA.C is a cluster heading. These are the individual standards under it.

• CCSS.Math.Content.1.OA.C.5

  Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).

• CCSS.Math.Content.1.OA.C.6

  Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8 + 6 = 8 + 2 + ...

01

What Students Need to Do

Students find sums and differences using numbers up to 20. They count on, count back, make ten, break apart numbers, and use related facts.

02

What Mastery Looks Like

Students solve addition and subtraction problems with totals and starting numbers no greater than 20. They use counters, drawings, equations, or mental strategies and explain their steps. They recall facts through 10 quickly and accurately.

03

Common Misconceptions

Students may count every object instead of counting on from the larger number. They may reverse subtraction numbers or confuse plus and minus signs. Some struggle to break apart numbers to make ten.

04

How to Assess It

Use this exit ticket: Solve 8 + 7 and 14 - 6. Draw or write how you solved one problem.

1. 01

   Give pairs 20 counters and number cards, then have them build and solve each addition or subtraction problem they draw.

2. 02

   Ask, "How could making ten help solve 8 + 6?" Have students draw and explain their strategy to a partner.

3. 03

   Play Fact Match with equation cards and answer cards, asking students to find matching pairs and explain each match.

4. 04

   Set up a class store with 20 play coins, then have students find totals and remaining amounts for simple purchases.

• CCSS.Math.Content.K.OA.A.5

  Fluently add and subtract within 5.

• CCSS.Math.Content.1.OA.A.1

  Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, wit...

• CCSS.Math.Content.2.OA.B

  The 2nd Grade version of this standard.