The act of splitting an object or value down into smaller parts.

Solve subtraction problems using knowledge of 10 and a bit

Maths

In this unit pupils will explain 11-19 as cardinal and ordinal numbers. They will double and halve numbers 6-9 and use addition and subtraction facts to add and subtract within 20. In the future unit pupils will explore the counting sequence for counting to 100 and beyond and represent the numbers from 20-99 in different ways, including marking the position on a number line. 

In prior learning, pupils will have looked for patterns and relationships in number, spotting connections and talking about what they notice. In this unit pupils will explain 11 to 19 as cardinal and ordinal numbers. They will double and halve the numbers 6 to 9 and use known facts to add and subtract within 20.

Composition of numbers 11 to 19

Jacob and Laura have collected 13 sticks at the park.
Laura has 3 sticks. Jacob has dropped his sticks. How many did he drop?

Which part-part-whole model matches this problem? Jacob collected some stones. He collected 15 stones but lost 5 of them. How many did he have left?

Which of these equations can be represented by this bar model?

Jacob and Laura collected 19 stones.
10 are brown and the rest are grey. How many are grey?
Which equation matches this problem?

Jacob had some cubes. Laura took 8 and he has 10 left.
How many cubes did he have at the start? Which equation with a missing number correctly matches this problem?

Laura has red, blue and yellow marbles. There are 17 marbles in total. 3 marbles are red and 7 marbles are blue. How many are yellow?

Which equation matches the part-part-whole model?

Jacob is going to hop 9 times. He has already hopped 5 times. How many more hops does he need to do?

Izzy is going to jump 10 times across the playground. She has jumped 6 times. How many more jumps does she need to do?

What is the missing part in the part-part-whole model?

This lesson will soon be taken down.

Solve subtraction problems using knowledge of 10 and a bit

Lesson outcome