Comparing Amounts

Overview

In this lesson (Lesson 5 of 15) students compare two small collections to decide which has more, less, or the same number of objects. They use everyday language and short explanations to justify their thinking.

Learning intentions

• WALT compare two collections by counting or matching one-to-one.
• WALT identify whether one collection has more, less, or the same number of objects.
• WALT explain our comparison using words like “more”, “less”, “same”, “equal”, and “because”.
• WALT show our thinking in a picture, model, or verbal explanation.

Success criteria

• I can match objects from one collection to the other to compare numbers.
• I can say which collection has more, less, or the same.
• I can justify my answer using “because” and a counting or matching reason.
• I can count accurately when I need to.

Curriculum links

• Number and Algebra — number sense and place value: comparing and ordering small numbers (using one-to-one correspondence and counting).
• Reasoning — explaining how we know and justifying solutions using mathematical language.
• Communicating — sharing explanations with teachers and classmates using appropriate vocabulary.
• Te reo Matihiko (Maths language opportunity) — using “more”, “less”, “same/equal” in explanations.

Lesson structure (45 minutes)

1. 0–5 min · Warm-up counting quickfire. Teacher shows a small group of objects (e.g., 3 counters) and quickly asks: “How many? How do you know?” Students respond with finger counting and brief explanations.

2. 5–10 min · Hook with same amount surprise. Teacher places two plates: Plate A has 4 blocks spaced out, Plate B has 4 blocks but arranged differently. Teacher asks: “Do they have the same number? Tell me what you notice.” Students predict and then share one method they could use.

3. 10–25 min · Explore: compare collections. Teacher gives each pair of students two sets of objects (different and sometimes equal), plus a “match it” mat with two spaces. Students compare using one-to-one matching first, then count to confirm; they record using a simple drawing (or teacher scribe if needed).

• Teacher prompts: “What does matching show?” “Do you need to count to check?” “Which one has more/less/same?”

4. 25–35 min · Guided sharing: justify and learn from others. Teacher selects 3 student examples (one “more”, one “less”, one “same”). Students take turns explaining using sentence starters:

• “I know it has more because…”
• “They are the same because…”
• “I matched them one-to-one…” Teacher listens for counting accuracy, one-to-one correspondence, and clear comparison language.

5. 35–42 min · Teacher-led practice with increasing challenge. Teacher uses a “mystery comparison” slide or physical cards (no more than 5 objects per side). Students decide more/less/same, match or count to prove, then share the justification. Teacher focuses on misconceptions: when objects are spread out, students may think one side is “bigger” even if numbers are equal.

6. 42–45 min · Exit ticket (quick check). Each student completes one comparison: two boxes with 3–5 dots/counters. They circle “more / less / same” and say one short reason to the teacher (or show with a matching line).

Resources

• Small counters or cubes (enough for pairs)
• Two-colour counters or objects (optional for easier matching)
• “Match it” mats (two side-by-side boxes)
• Simple exit ticket sheets (more/less/same with 3–5 objects)
• Glue sticks and paper for quick drawings
• Object cards or number cards (for teacher demonstrations)
• A timer for transitions (visual timer helpful)
• Sentence starter cards (“I know because…”)

Assessment

• Teacher observes during pair work: whether students use one-to-one matching correctly and use comparison language.
• Teacher checks explanations in guided sharing: students can justify using counting or matching (“because…”).
• Exit ticket: accurate choice of more/less/same and an understandable reason.

Differentiation

• Support:
• Provide pre-printed sentence starters and picture word bank (more/less/same/equal).
• Use fewer objects (3–4) for students who need more practice and keep “matching lines” visible.
• Offer a one-to-one matching frame (fixed slots) to reduce counting errors.
• Extension:
• Include a “trick layout” where one side is taller/spaced out but the number is the same, prompting deeper justification.
• Ask students: “Can you make yours match exactly? How do you know it matches?”
• EAL/SEN considerations:
• Allow responses through pointing, drawing, or teacher scribing at first; gradually require the “because” reason.
• Repeat key vocabulary and model full sentences before independent attempts.