A weaker class pattern in quantity understanding may affect comparison, estimation, grouping and later number work. Pupils can sometimes count or calculate correctly without having a secure sense of how large a quantity is or whether an answer is plausible.

Build magnitude into ordinary maths teaching before moving directly to written notation.

Ask pupils to see and compare quantity

Use structured objects, dot patterns, ten frames, number lines or measures. Ask questions such as:

• Which quantity is greater, and how do you know?

• What group did you see first?

• Is the answer likely to be nearer 20 or 200?

• What would be a sensible upper and lower estimate?

Give pupils time to explain how they saw the quantity. Do not turn the activity into a speed competition.

Estimation 180 (free) has over 200 visual estimation tasks, made by Andrew Stadel for US Grades 3 to 8 (about Years 4 to 9). One task makes a quick starter: pupils give a best estimate and a range they are confident in before you discuss the answer. It is American, so check the units and context of a task before you use it.

Move from judgement to exact value

A useful sequence is:

1. show a structured quantity briefly;

2. ask for an approximate amount or comparison;

3. reveal it again and discuss groups or parts;

4. count or calculate the exact amount;

5. connect it to the written number.

For example, show 18 counters arranged as three groups of six. Ask pupils what they notice before counting individually, then connect the groups to 3 × 6, 18 and nearby quantities.

In Secondary maths, use the same principle with scale, measures, fractions, percentages or standard form. Ask pupils to predict a plausible range before calculating.

Match emphasis to the class pattern

Where quantity understanding is slightly weaker, include one brief magnitude question in the lesson. Where it is lower, plan regular comparison and estimation alongside exact calculation.

When some pupils need more

This is whole-class magnitude teaching. Pupils who still count every item one by one, or cannot say which of two amounts is larger without counting, may need focused work with structured quantities.

Further guidance

• EEF: Improving Mathematics in Key Stages 2 and 3

• NCETM classroom resources

Talamo has no commercial relationship with any of the organisations named here. We suggest them only because we think they could be useful to schools.