Number confidence

Represent small totals, split a number into parts, and use subtraction to solve an everyday space problem.

About 15 minutes

Read the example, try the task, then open the self-check. No purchase or AI generation required.

LESSON 01

Count each item once

Counting works when each object is matched to one number word. Move, point to, or mark each item as you count so it is included once. The final number tells you how many objects are in the group. Rearranging the same objects does not change the total. For practice, drawings work just as well as objects you can move.

Point to, move, or mark each item so you count it once.
Check that rearranging the same objects leaves the total unchanged.

A worked example

Draw eight circles in a row and count them. Redraw them as two rows of four. There are still eight circles: 4 + 4 = 8. The arrangement changed, but no circles were added or removed.

Now you tryDraw six dots. Count them once, then circle them in pairs. How many pairs are there, and how many dots altogether? Use a finger to keep track.

Check your practice

Six dots form three pairs. Count 2 + 2 + 2 = 6. Grouping the dots has not changed their total.

LESSON 02

Break a total into useful parts

A number can be split into different parts without changing its total. Seeing those parts helps with addition and with checking an answer. Use dots, a drawing, or a short number sentence to show your thinking. Start with a total you can picture easily, then move one item from one group to the other and notice what stays the same.

Use drawings or number sentences to split a total into two parts.
Move one item between groups and notice that the whole stays the same.

A worked example

Ten seats can be pictured as seven occupied and three empty: 7 + 3 = 10. If two more people sit down, there are nine occupied and one empty: 9 + 1 = 10. There are still ten seats.

Now you tryDraw ten squares. Shade six and leave four clear. Write the addition sentence. Then shade one more square and write the new sentence.

Check your practice

First: 6 + 4 = 10. After shading one more: 7 + 3 = 10. The two parts change, but the total stays ten.

LESSON 03

Find what is left and check it

Subtraction can tell you what remains when part of a total is used. First identify the whole amount and the part already taken. Draw the situation if the words feel confusing, then subtract. Check the answer by adding the used part and the remaining part together. That sum should match the original total, giving you a second way to test your reasoning.

Identify the whole and the used part, then subtract to find what remains.
Check by adding the parts back together and include the unit in your answer.

A worked example

A room has twelve chairs and eight guests are seated. Empty chairs: 12 − 8 = 4. Check: 8 occupied + 4 empty = 12 chairs. The answer is four chairs, so include the unit in your response.

Now you tryThere are fifteen spaces on a display and nine pictures already placed. How many spaces remain? Draw, subtract, and check with addition.

Check your practice

15 − 9 = 6 spaces remain. Check: 9 pictures + 6 empty spaces = 15 spaces.

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Original Junction practice lessons, assisted by AI and reviewed for this page. Examples are illustrative. Self-reported progress is not a grade, certificate or professional qualification. External resources have their own terms.