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👩‍🏫 Teaching Guide • Grade 1

How to Teach Addition to 20

First graders need addition practice that moves from concrete objects to mental strategies. This guide focuses on counting on, making 10, and using story problems that connect addition to everyday life.

📐 Standards Alignment

1.OA.A.1 CCSS.MATH

Use addition and subtraction within 20 to solve word problems.

1.OA.C.6 CCSS.MATH

Add and subtract within 20 using strategies such as counting on and making ten.

1.OA.D.7 CCSS.MATH

Understand the meaning of the equals sign and determine if equations are true or false.

📦 Materials Needed

  • Counters or small blocks
  • Number line 0-20
  • Ten-frame cards
  • Whiteboard or paper

🎯 Teaching Strategies

💡
Start with Real Objects Let students build both groups with counters first. After they model the problem, ask them to describe what happened when the groups were joined.
💡
Teach Counting On Explicitly Model how to keep the first number in your head and count on from there. This is one of the biggest shifts from kindergarten counting.
💡
Use Making 10 for Harder Facts When a problem is close to 10, show how taking 1 or 2 from the second addend can create a friendly number first.

⚠️ Common Misconceptions

❌ Misconception: Students recount every object from 1

✅ Correction: Encourage them to say the first number once, then tap or hop as they count on.

❌ Misconception: Students think the equals sign means "the answer comes next"

✅ Correction: Read equations aloud as "is the same as" so students understand both sides are equal.

📊 Differentiation Tips

Struggling

Keep totals within 10 at first and use counters or fingers every time.

On-level

Mix equations, number lines, and story problems so students practice addition in more than one format.

Advanced

Challenge students to solve the same problem with two strategies, such as counting on and making 10.

🚀 Extension Activities

  1. Play addition war with cards numbered 0 to 10.
  2. Build a classroom chart of doubles facts.
  3. Write your own addition stories using toys or snack items.