Subtract by bridging 10 using number bonds to 10 - Teaching Presentation - Year 1

This presentation provides three days of teaching that cover the objectives:

• Subtracting, bridging 10.
• Sort calculations according to whether they will bridge 10 or not

It includes starter activities, whole class teaching, group activities, practice sheets and mastery questions. It can be used on a variety of interactive whiteboards.

Day 1 Teaching
Show 15 beads. What is 15 subtract 5? Agree that we need to take away 5 beads. Do we need to count back? No! We can take 5 from 15 without doing any counting! Show that we can use this to do 15 – 8. First we subtract 5 (to get to 10) then we take away another 3. Do we know 10 – 3? Yes! Record 15 – 8 = 7. Repeat for 14 – 6, 13 – 7 and 17 – 9.

Day 2 Teaching
Show children a bead bar. Use this to model 12 – 5 and then 13 – 4. In each case show children how we can target the 10, then use number bonds to do the second part. Draw steps on a 0-20 beaded line. Reinforce by doing 14 – 5 and 14 – 6.

Day 3 Teaching
Present some subtractions on cards, e.g. 11 – 3, 11 – 6, 15 – 3, 15 – 6, 13 – 2, 13 – 4, 16 – 3, 15 – 6, 15 – 4. Which do you think will have an answer more than 10? Discuss with children how they can tell. What do we look at? Is the number being taken away larger or smaller than the 1s digit in the teens number? When we can see the answer is going to be less than 10, we can use ‘Target the 10’. We can call this T10 for short. If the answer is going to be more than 10, we can count back or use a number fact to help.

This teaching is part of Hamilton’s Year 1 More Addition and Subtraction block. Each Hamilton maths block contains a complete set of planning and resources to teach a term’s worth of objectives for one of the National Curriculum for England’s maths areas.