Sample Week: Lesson 5

Place Value - Teen Numbers

 

OBJECTIVES:

To partition ‘teen’ numbers into 10 and 1s.

RESOURCES:

100-bead string | Download 1-20 Washing Line numbers

| Download 1-20 Number Cards

VOCABULARY:

teen number | partition (split into tens and ones) | tens | ones | count on

 

WhatGetReady.png What to Get Ready

Print out and cut out the Download 1-20 Number Cards

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Introduction Icon.png Introduction

Count from 1 to 20 pointing to numbers on a washing line as you do so. Repeat several times so that your child joins in confidently.

Repeat the activity, but this time start from different places on the washing line, for example, 6 or 11.

Ask your child to take off their shoes and to stretch out their legs so all 10 toes are in front of them. Wiggle your toes and count them!

Now ask them to hold up 3 fingers.

10 toes and 3 fingers – how many fingers and toes do you have altogether?

Discuss with them how they might have worked this out.

Now ask your child to hold up 5 fingers to add to their toes to make 15. Repeat several times with other teen numbers.

Give your child the number cards from 10-20.

Show a teen numbers on the 100-bead string and ask your child to hold up the correct number card.

Point out how there are 10 beads, and then another number less than 10 each time.

Apply.png Apply

Hold up 10 fingers. Ask your child to hold up any number of fingers from 1-10.

Ask: ‘How many fingers are showing altogether with mine and yours?’ Discuss.

Discuss how it is easy to start with 10, put this in their heads and then to count on the second number using their fingers.

Write this number down.

Challenge your child to repeat the activity until they think they have made every number from 11 to 20.

Encourage them to discuss any patterns they can see, or interesting findings.

When your child has made all of the numbers, check by counting from 10 to 20.

Play a quick fire game to check understanding by calling out teen numbers for your child to make. Your child should show 10 straight away and then show the ‘extra’ numbers.

This video demonstrates using the bead string to show adding numbers to 10, and writing the number sentences. 

Stretch Icon.png Extra Challenge

This activity can be made a little more challenging by asking your child to write down the matching number sentence each time they make a new teen number.

For example: 10 +2 =12

Or:

Make numbers with rods of 10 red cubes and some white cubes. Can your child write these numbers?