**Introduction**

Start the lesson by counting from 1 to 20 and back again. Then invite children to choose a number from 1 to 20 and start the counting from this number, continuing to twenty. Explain to the children that they are going to be working on addition.

Introduce two small sets of objects and count each. Ask the children how many will be there be when we put the sets together?

Combine the sets and count the total. Talk about other ways in which this problem might have been solved.

Return the objects to their original two sets. Count one of the sets and remind the children how to 'hold on to that number', counting on from that as the other set is added.

Link this idea of counting on to addition by counting on along a number line, reminding children about the one step - one count rule. Talk through the activities which different groups of children are going to carry out.

### Group Activities

**Activity 1** - Children working independently

Try out the Numbertime Website Game, Test the Toad.

**Activity 2** - Children working independently

Complete the Numbertime Website 'Print and Do' Sheet, Tanto's Hiding Place.

**Activity 3** - Children working with a teacher

Play the following "Number Hunt" addition game. You will need to provide two dice, each with numbers 1 to 6. Ask children what the highest and lowest scores are which they could throw using both dice.

Each child then draws a number line to show the range of possible scores (in this case 2 to 12).
The children take turns to throw the dice, crossing out the total score from their line. The winner is the first to cross out three consecutive numbers.

As the game progresses ask the children to describe the addition sums they have generated. Use a wide range of vocabulary.

You have thrown a 2 and a 5:

What is the total? What is 2 plus 5?

What number do you get if you add 2 to 5? What is 2 count on 5?

Use the game to introduce the idea of the commutativity of addition.

You have thrown a 2 and a 5. Will you make the sum 2+5 or 5+2? Does it matter?

Talk about the number of ways in which different numbers can be made:

You need to make a 7 to win the game.

How many ways could you do that with these two dice?

Differentiate the game by varying the dice which you use. Use multi-sided dice to extend more able children, or label an ordinary die with six consecutive but larger numbers. Draw the attention of able to children to instances of doubles and near doubles as they are thrown.

Support less able children by labelling one or both of the dice 1, 1, 2, 2, 3, 3.

Provide counting apparatus or additional number lines as further practical support.

### Plenary

Remind the children that they have all been adding numbers, and some people have been recording their work. Invite each group to briefly explain what they have been doing to the rest of the class, showing samples of their work.

Finish the lesson by singing a 'backwards' version of a favourite traditional number song.

No currant buns in a baker's shop,

Round and fat with sugar on the top

A boy came by with a bun one day

Put it in the shop and then ran away