Vocabulary

one less than, one more than

Resources

Stage 1

Bag or tin and some counters (a tin helps to create opportunity for the listening aspect to counting, so it is good to use counters that will make a noise as they are dropped into the tin)
Number tracks to 30 (one large enough for all children to see and table-top versions, one between two children)
Sets of number cards 0–29 (pairs of children need a selection within the range – so perhaps need five or six sets)
Teddy counters (one teddy between two children) 

Stage 2

Bag or tin as used in stage 1
Number tracks to 30 (one large enough for all children to see and table-top versions, one between two children)
Sets of number cards 2–31 (pairs of children need a selection within the range – so perhaps need five or six sets)
Teddy counters (one teddy between two children)

Plenary

Set of number cards to show children (some numbers in range 0–30) and a bag to put them in
Whiteboards and pens for children to use

Potential challenges

Children may have more difficulty with identifying ‘one less than’ than ‘one more than’. The language and understanding of ‘more than’ are likely to be part of their experiences in and out of school; children often have less experience of the idea of ‘less than’.

Some children may only be able to identify ‘one more than’ by counting on, starting from 1. If this is the case, then maybe these children need more experience of counting on from any given start number. It is likely that these children will struggle to identify ‘one less than’ and these children will need more experience of counting back in ones starting from different numbers. Number tracks can be used to help them to count forwards and backwards.

Ways the lesson could be adapted

The lesson could start with children being given number cards and getting in order, followed by some questioning about which number is one more than or one less than identified numbers. After they have put themselves in order, children could be asked to stand forward if their number is ‘one more than . . .’ and so on, and continued in this way with ‘one less than’ introduced through a similar activity. It is important to ask questions in a way that will encourage children to use the appropriate language.

The main part of the lesson could consist of children being given number tracks with some numbers missing and they have to fill in the missing numbers. However, children can sometimes complete this type of activity without engaging with the idea of ‘one more than’ or ‘one less than’; they can simply count their way up and down the number track.

Different number problems can be used with children to apply the ideas of ‘one more than’ and ‘one less than’. For example:

There are four people on the bus. One more gets on. How many people are now on the bus? It would be important to ‘tell the story’ using numbers only. One more than four is five, moving on to establishing the number sentences, as described in the next section.

There are ten children in the toy shop. One goes out. How many children are there now in the shop?

You could ask children to make up stories using the phrases ‘one more than’ and ‘one less than’. This is often a really good way to assess the depth of children’s understanding and also give them some ownership of their learning.