Thinkabara

🧮 1st Grade · Math1.NBT.C.4Unit 8: Adding & subtracting with tens

Adding ones without regrouping

Google Classroom

🎯 Objective: Students add a one-digit number to a two-digit number when no new ten is needed (42 + 5).

Lesson outline

  1. Build 42 and add 5 ones.
  2. Explain why the tens stay the same.
  3. Practice with blocks and drawings.
  4. Exit: 63 + 4.

Lesson 2 of 5 in this unit. In the Lesson Planner this lesson takes 1–3 class periods depending on your timetable: day 1 introduce & model, then practice, small-group reteach and a quick check.

📐 Standard

1.NBT.C.4

Common Core State Standards for Mathematics, Grade 1 — typical US scope & sequence

🏁 Unit goals

  • Add a two-digit number and a one-digit number or a multiple of 10
  • Subtract multiples of 10

✅ Check for understanding

End with the exit ticket in the outline. Sort answers into got it / almost / not yet and start the next lesson with a 5-minute reteach for the “not yets”.

Practice & resources on Thinkabara

🎯 Practice: Place value to 120📚 All 1st Grade skills🎮 Learning games⚡ Capy Live class quiz

🗓️ Plan the whole year like this

Add 1st Grade Math to your free Lesson Planner: enter your timetable once and every period shows the next lesson, skipping weekends and school breaks.

Add to my planner See the year’s sequence

More lessons in “Adding & subtracting with tens”

  1. Adding tens
  2. Adding ones without regrouping
  3. Making a new ten
  4. Subtracting tens
  5. Two-digit story problems

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