Foundations of Mathematical Thinking · Senior Infants

Active learning ideas

Comparing Sizes and Amounts

Active learning works well for this topic because young children learn best through touch and movement, not just listening. Comparing real objects helps them connect abstract ideas like 'longer' or 'heavier' to things they can see and move around.

• NCCA Curriculum Specifications
• NCCA: Junior Cycle - Measurement - M.4

• 20–35 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Stations Rotation
• 30 min · Pairs

Block Tower Hunt: Taller Comparisons

Children build a class block tower, then hunt classroom or outdoor items taller than it using string or rulers in cm. Pairs measure finds and record with drawings. Share tallest items in whole class circle.

Can you find something taller than this block tower?

Facilitation Tip

During Block Tower Hunt, have students stand back from their towers to see differences in height before measuring with hands or strings.

What to look for

Provide students with a collection of classroom objects (e.g., crayon, book, pencil). Ask them to select two objects and state which is longer or shorter, then measure both with a ruler to verify their comparison.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 02

• Stations Rotation
• 25 min · Small Groups

Balance Scale Races: Mass Check

Set up stations with balance scales, gram weights, and toys. Pairs race to find heavier objects by balancing against known masses, noting conversions like 50g equals five 10g cubes. Discuss surprises.

Which group has more , let us count to check.

Facilitation Tip

In Balance Scale Races, ask pairs to take turns placing gram weights on the scale and predicting which side will go down before testing.

What to look for

Present two different-sized containers. Ask: 'Which container do you think holds more water? How can we check?' Guide students to use a measuring jug to pour water from the smaller container into the larger one, or vice versa, to confirm their predictions.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 03

• Stations Rotation
• 35 min · Small Groups

Pouring Stations: Capacity More or Less

Provide varied containers and measuring jugs in litres. Small groups pour water to compare which holds more, estimating first then measuring accurately. Chart results on class graph.

Is this box bigger or smaller than that one , how do you know?

Facilitation Tip

At Pouring Stations, provide clear containers with litre markings and ask students to pour slowly while counting aloud to avoid spills.

What to look for

Give each student a strip of paper. Ask them to draw a line that is exactly 1 decimetre long. Then, ask them to draw another line that is shorter than 1 decimetre and label its approximate length in centimetres.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 04

• Stations Rotation
• 20 min · Pairs

Box Size Showdown: Volume Debate

Pairs compare classroom boxes by length, width, height in cm. Debate bigger or smaller with evidence, converting measurements. Vote on class biggest box.

Can you find something taller than this block tower?

Facilitation Tip

During Box Size Showdown, encourage students to arrange boxes by estimated size before measuring length, width, and height with rulers.

What to look for

Provide students with a collection of classroom objects (e.g., crayon, book, pencil). Ask them to select two objects and state which is longer or shorter, then measure both with a ruler to verify their comparison.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

A few notes on teaching this unit

Teachers should model precise language when comparing, such as 'This tower is 5 hand spans tall, and that one is 7.' Avoid skipping steps like estimating before measuring, as this helps students value accuracy. Research shows that concrete experiences with familiar objects build stronger measurement foundations than abstract rules. Use peer talk to let students explain their findings, as explaining reinforces understanding.

Successful learning looks like students using clear language to compare sizes and amounts, measuring with tools correctly, and explaining their reasoning with evidence. They should move from guessing to using units like centimetres, grams, and litres with confidence.

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Watch Out for These Misconceptions

• During Balance Scale Races, watch for students who assume larger objects are always heavier.

  After Balance Scale Races, ask students to compare a feather and a rock on the scale, then discuss why size does not always match mass. Have them record findings on a class chart with photos of the objects.

• During Block Tower Hunt, watch for students who count hand spans or blocks inconsistently when comparing lengths.

  During Block Tower Hunt, provide rulers marked in centimetres and demonstrate how to align the zero mark with the base of the tower. Ask students to recount their measurements together in pairs to check for accuracy.

• During Pouring Stations, watch for students who think tall containers always hold more than short, wide ones.

  During Pouring Stations, give students two containers of different shapes but similar volume. Ask them to pour water from one to the other to test their predictions, then mark the litre level on both containers to visualize the space inside.

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Methods used in this brief

• Stations Rotation