TEACHER EDITION

Order Numbers

Grade 1 · Lesson 3 · Dimensions 1A p.10
Math Book 1 · sheet 3
Warm-up — yesterday: The Number 0
How many are in the empty box?
0

What we are learning

Numbers have an order, and each one is exactly 1 more than the one before it.

How it is done — keep this beside you

These steps stay on your page while you work. If you get stuck, find the step you are on and read it again before you put your hand up.

1
I write the numbers I know, out of order.
5 2 8 1
2
Which is the least? I count up from 0 to find it: 0, 1 — there it is.
5 2 8 1 5 2 8 1 → 1
3
Next least is 2.
5 2 8 1 5 2 8 1 → 1 → 1 2
4
Then 5.
5 2 8 1 5 2 8 1 → 1 → 1 2 → 1 2 5
5
Then 8. Least to greatest.
5 2 8 1 5 2 8 1 → 1 → 1 2 → 1 2 5 → 1 2 5 8

Practice

I DOteacher builds it, nothing erased
Put in order, least to greatest: 4, 1, 3
  1. Count up: 1 comes first.
  2. Then 3.
  3. Then 4.
  4. 1, 3, 4
WE DO 1together, on whiteboards
Put in order, least to greatest: 7, 2, 5
Find the least first. Boards up when you have all three.
  1. 2, 5, 7
WE DO 2together, on whiteboards
Put in order, least to greatest: 6, 0, 9
Careful — one of these is the zero we met yesterday.
  1. 0, 6, 9
YOU DOindependent, from the book
Book 1A p.10 — the Do section, clipped onto the slide
the book page
Ask yourself: “Did I start from the least, or from the one I noticed first?”
Watch for
Including 0 is deliberate. A child who puts it last has not connected yesterday's lesson to this one, which is exactly what the warm-up was testing.