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Parent guide · Grade 1 Math · Unit 6

Lesson 6.2 Two-Digit + One-Digit

Written for the parent. Read the Say this lines aloud as they are, or in your own words. Answers for you are marked Listen for.

At a glance

Time
5 sessions of 20–25 minutes
Goal
Add a one-digit number to a two-digit number.
You need
  • A few real coins
  • Craft sticks and rubber bands
  • Pencil and crayons
Print
Worksheet A · Worksheet B · the lesson page

Steps

  1. Do this: Ask these out loud. Your child answers out loud; no paper needed.

    • Ask: “1 + 7” Listen for: 8
    • Ask: “5 + 3” Listen for: 8
    • Ask: “7 + 2” Listen for: 9
    • Ask: “6 + 8” Listen for: 14
    • Ask: “2 + 2” Listen for: 4

  2. Say this: “For 34 + 5, add the ones: 4 + 5 = 9. The tens stay the same: 39.”

    Say this: “If the ones make more than 9, make a new ten: 38 + 5 = 43.”

    Say this: “Ones: the single units.”

  3. Show: 54 + 1 = ___

    Say this: “Start at 54 and count on 1: 55.”

    Say this: “54 + 1 = 55”

    Answer: 55

    Show: A Roman legion marched 26 miles one week and 1 miles the next. How far did it march?

    bar model

    Say this: “Unknown: the total.”

    Say this: “Bar model: two parts, 26 and 1; the whole is unknown.”

    Say this: “Equation: 26 + 1 = ?”

    Say this: “26 + 1 = 27”

    Say this: “Answer: It marched 27 miles.”

    Answer: 27 miles. It marched 27 miles.

  4. Do this: Your child does these with you. Let them try first; help only after a real try.

    Ask: 30 + 3 = ___

    Listen for: 33

    If stuck: Start at 30 and count on 3: 31, 32, 33.

    Ask: 21 + 7 = ___

    Listen for: 28

    If stuck: 21 + 7 = 28

    Ask: 53 + 6 = ___

    Listen for: 59

    If stuck: 53 + 6 = 59

    7 more practice items on the lesson page, and on Worksheet A and Worksheet B.

    • Adding the 5 to the tens digit.

  6. Price toys at 10¢, 20¢ … 90¢. Your child pays with dimes and says the total of two toys, then the change from $1.

  7. Say this: “Tell me what you learned today. Show me with your hands or the counters if you like.”

    Listen for: Add a one-digit number to a two-digit number.

  8. Count by tens from any number: 3, 13, 23 … and back down.

Spread over the week

5 sessions of 20–25 minutes. Stop while it is still going well.

  1. Session 1. Warm-up, then teach the new idea (steps 1 and 2).
  2. Session 2. Warm-up again, then show how with the examples.
  3. Session 3. Practice together, then play the game.
  4. Session 4. More practice on the worksheet, and the daily habit.
  5. Session 5. Quick check: narration and a few practice items. Move on when it is mostly right.