Parent guide · Grade 2 Math · Unit 2

Lesson 2.2 Expanded Form

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: Write numbers in expanded form.
You need: Pencil and crayons
Print: Worksheet A · Worksheet B · the lesson page

Steps

Warm-up
Do this: Ask these out loud. Your child answers out loud; no paper needed.
- Ask: “What number is one hundred more than 404?” Listen for: 504
- Ask: “What number is one hundred less than 422?” Listen for: 322
- Ask: “What number is one hundred less than 227?” Listen for: 127
- Ask: “What number is one hundred less than 247?” Listen for: 147
- Ask: “What number is one hundred less than 459?” Listen for: 359
Teach the new idea
Say this: “Expanded form shows what each digit is worth: 352 = 300 + 50 + 2.”
Say this: “Skip a place that has a zero: 407 = 400 + 7.”
Say this: “Expanded form: a number written as the sum of its place values, like 300 + 50 + 2.”
Show how
Show: Write 342 in expanded form.
Say this: “Write each digit times its place value: 300 + 40 + 2”
Say this: “Check: 300 + 40 + 2 = 342”
Answer: 300 + 40 + 2
Show: 4 hundreds, 6 tens and 9 ones make what number?
Say this: “4 × 100 = 400”
Say this: “6 × 10 = 60”
Say this: “400 + 60 + 9 = 469”
Answer: 469
Practice together
Do this: Your child does these with you. Let them try first; help only after a real try.
Ask: What is the value of the digit 9 in 193?
Listen for: 90
If stuck: The 9 is in the tens place.
Ask: What is the value of the digit 7 in 975?
Listen for: 70
If stuck: The 7 is in the tens place.
Ask: What is the value of the digit 7 in 597?
Listen for: 7
If stuck: The 7 is in the ones place.
7 more practice items on the lesson page, and on Worksheet A and Worksheet B.
Watch for
- Writing 3 + 5 + 2. Each digit stands for its place value.
Game: Biggest Number
Each player draws three digit cards and arranges them to make the biggest number possible. Read it aloud. Biggest number wins.
Narration
Say this: “Tell me what you learned today. Show me with your hands or the counters if you like.”
Listen for: Write numbers in expanded form.
Daily habit
Count by hundreds to 1,000, by tens from any number, and by fives to 100.

Spread over the week

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

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