Put numbers 0 to 20 in order

What it looks like when your child can do it

• — Given a shuffled stack of cards from 0 to 20, your child lays them in one row in order.
• — Shown 7, a blank card, and 9, your child says the blank is 8.
• — Asked for the neighbor just before 12, your child says 11.

How to teach it at the kitchen table

1. 01

   Make a number path

   Write the marks 0 to 20 on sticky notes or paper scraps. Lay them in one row, left to right, along the floor or a hallway. The book calls this a number path.

2. 02

   Walk the path, saying each mark

   Your child steps or points along the path and says each mark out loud. No mark gets skipped, and every step is the next number.

3. 03

   Find the neighbors

   Pick a mark, like 3. Ask for the neighbor just before it, 2, and the neighbor just after it, 4. Then try one in the teens, like 13, where the marks look alike and the neighbors matter more.

4. 04

   Flip a card and name the hole

   Turn one card face down while your child looks away. They name the hole from the marks on each side of it, without starting back at 0.

You will need: Twenty-one sticky notes or paper scraps, marked 0 to 20, plus two blank ones · A marker

Try it together

1. Try 1

   Lay out 2, 3, a blank card, then 5. Ask what goes in the blank.

   Listen for  4.

2. Try 2

   Lay out 9, a blank card, then 11. Ask for the missing mark.

   Listen for  10. This is the step from one-mark numbers into two-mark numbers, so it is worth a second look.

3. Try 3

   Hand your child the cards 17, 15, 18 and 16 in a mixed-up pile. Ask them to put the cards in order.

   Listen for  15, 16, 17, 18.

4. Try 4

   Point to 1 and ask for both of its neighbors.

   Listen for  0 just before and 2 just after. Children often forget that 0 has a place on the path.

5. Try 5

   Lay out 11, 12, 14, 15. Ask whether anything is missing.

   Listen for  Yes. 13 is missing, between 12 and 14.

Watch for

• — Writing a teen backwards, like 31 for 13. Point to the 1 and remind your child that in the teens it always sits on the left.

If it is not there yet

• — Shorten the path to 0 to 10 until that part is steady, then add the teens a few at a time.
• — Go back to counting on out loud: say a number and ask for the next one, with no cards at all.

A few days of this is normal, and it is time well spent. The lesson will still be there, and it will go faster.

Where this skill comes up

• Zig and Zag Count to Twenty · Lesson 25

  How Many in the Pile?

  Needs it because writing the mark for a counted pile needs the path of marks already in order.