💡 Lesson Overview
This lesson teaches students one of the most important early-math skills: verifying counts using two different strategies.
Students will:
- scan their brick pile
- choose and build a small model
- count the bricks they used
- recount using a different method
- explain how they know the final total is correct
- supports purposeful decision-making when choosing a model
This develops accuracy, metacognition, comparison language, and mathematical reasoning.
Aligned with Common Core (1–2), Cambridge Primary (Stage 1–2), and IB PYP Math.
🎯 Today's Goal for Students
👩🏫 What to tell your students at the start of the lesson:
"Today we are learning to check our counting. We will count our bricks one way, then count them again using a different way. If both counts match, we know our answer is correct. This is what mathematicians do — they always check their work!"
💡 This simple statement helps students understand the purpose of the lesson and makes their actions more meaningful and focused.
🎯 Learning Goals
Number Sense
Count objects accurately up to 20+
Verify totals using two different counting strategies
Mathematical Reasoning
Explain why two counts match or do not match
Identify and correct counting mistakes
Problem Solving
Use substitutions and flexible thinking during building
Adjust strategies to reduce errors
Communication
Use vocabulary: recount, verify, match, total, strategy, same, different
Collaboration
Work cooperatively when counting and checking
🧠 Skills Developed
| Domain | Focus in this Lesson |
|---|---|
| Mathematics | Counting, recounting, strategy comparison |
| Metacognition | Error detection and explanation |
| Visual Thinking | Using models as data sources |
| Communication | Describing strategies and totals |
| Collaboration | Turn taking, shared group roles |
| Problem Solving | Choosing efficient ways to recount |
🧰 Teacher Preparation
Materials per team (typically 2–4 students; up to 5–6 if needed)
200–300 mixed LEGO® bricks
1 device with Brickit App for Schools
Mini whiteboard or recording sheet
Markers
Student Recording Sheet – Count & Verify
Teacher Observation Checklist
Before class
Prepare sample counting strategies on the board: count by ones, count by colour groups, count by 2s or 5s, recount in a different order
Pre-scan one practice pile to check lighting
This lesson also supports strategy awareness — children observe how others sort, count, and group materials and may choose strategies that work for them.
This lesson encourages purposeful model choice — students learn to select a model that interests them and is appropriate for the time available.
📝 Teacher Notes — Why We Build First
Every lesson begins with: Sort → Scan → Choose → Build.
This routine:
- reduces chaos, builds motivation
- improves spatial reasoning
- provides a concrete model for mathematical exploration
📄 Student Recording Sheet
Print this worksheet for each student or group:
Lesson 1.2 – Checking and Verifying Counts
Name: _____________________ Date: _______________
1. First count: ______
2. Second count: ______
3. Did the numbers match?
☐ Yes ☐ No
4. Strategies I used:
☐ counted by ones
☐ counted in groups
☐ counted by colour
☐ used a different order
☐ other: ___________________
5. My equation:
________ + ________ + ________ = ________
6. How I checked my work:
7. Draw or describe your model:
📘 Lesson Flow
🧺 Sort the Pile
Duration: 5–8 minutes
👩🏫 Instructions
"Before we build, let's organise our bricks. Sort by an attribute."
"If you choose colour, put similar shades together — all blues in one group, all yellows in another. No need for exact shade matching."
"You can sort by colour families, shape, height, or number of studs. Choose what helps you count more accurately."
"Do not aim for perfect sorting. If bricks are connected, leave them together."
👧👦 What You Need to Do
- Sort by chosen attribute (colour families, shape, height, or studs)
- Do not aim for perfect sorting
- Identify which sorting pattern will help recount faster
- If you see a sorting strategy you like, try it
👩🏫 Teacher Focus
- Ask: "Which sorting rule will help your team count more accurately?"
- Ask: "Is it easier to recount when bricks are sorted?"
- Reinforce: Sorting is mathematical thinking — grouping, comparing, organising
🟦 Teacher Tip
Sorting is a warm-up, not a requirement. It helps organise materials and activates attention. Connected bricks can stay together. Multi-colour bricks can go in mixed groups or by dominant colour — both choices are fine.
🔁 If students struggle…
- Remind: "Similar colours go together — no need for exact matching."
- If bricks are hard to separate: "Leave them together — that's fine."
- If a student is stuck: "Try sorting by shape instead."
📝 Teacher Notes
- Sorting is not required for the Brickit scan and does not need to be exact.
- If some bricks are tightly connected, leave them together — perfection is not required.
- If a brick has more than one colour (windows, wheels), place it in a mixed-colour group or choose the dominant colour. Either choice is acceptable.
- Sorting helps children notice attributes, organise materials, and prepare for counting. Its purpose is cognitive activation, not correctness.
- Children may use different sorting strategies. Encourage noticing how others work and trying new strategies. Strategies are optional — accuracy in counting is the goal.
📷 Scan & Choose a Model
Duration: 5–8 minutes
👩🏫 Instructions
"Spread your bricks into one flat layer — one brick thick. This helps Brickit see everything."
"Now scan with the Brickit App. Look at the models it suggests."
"Choose a model your team likes, can build, and can build quickly — about 5–7 minutes."
"Brickit recognises shape and size, not colour. You can use any colours you have. Substitutions are correct and encouraged."
📋 Model Selection Rule
A model is "just right" if:
- students LIKE it
- they CAN build it (not too many tiny parts)
- they can build it QUICKLY (5–7 minutes)
- approx. 8–15 bricks (if visible in app)
- simple shape, no rare bricks
- substitutions are expected
👧👦 What You Need to Do
- Spread bricks on a flat surface (one layer thick)
- Scan with the Brickit App
- Look at suggested models
- Choose a model that feels "just right"
👩🏫 Teacher Focus
- Encourage choice based on interest, challenge level, clarity of required pieces
- Ensure each team makes their own choice
- Reinforce: Every choice is valid
- If your Brickit shows piece-count, guide toward 8–15 bricks
🟦 Teacher Tip
Children choose by interest first. Guide gently toward models they can build in 5–7 minutes: one clear object, few tiny pieces, visually simple.
🔁 If students struggle to choose…
- Remind the three rules: LIKE it, CAN build it, QUICK to build
- Help find a simpler model if current choice is too complex
- Say: "If it feels 'just right', that's perfect."
⚠️ If students struggle to build
- Switch to a simpler model
- Freeze the build "as is" and move to math
- Move to math even if model is unfinished — the goal is mathematical reasoning, not perfect building
📝 Teacher Notes
- The colour of the suggested Brickit model does not matter. Children may build using any available colours.
- If a piece is missing, students should choose a similar size/shape — this is correct problem-solving.
- If your Brickit version shows piece-count, aim for 8–15 bricks. If not, guide using visual simplicity.
- Sorting and rebuilding do not need to be perfect. The goal is mathematical reasoning, not precision.
🧱 Building the Model
Duration: 8 minutes
👩🏫 Instructions
"Now build your chosen model. Work together."
"If a piece is missing, find a similar one — same size or shape. That's correct problem-solving."
"If you're stuck, ask your team for help."
👧👦 What You Need to Do
- Build collaboratively
- Adjust model if needed
- Help each other find pieces
- Substitute missing pieces with similar shapes/sizes
👩🏫 Teacher Focus
- Observe problem-solving strategies
- Support teams that struggle with substitutions
- Celebrate creative adaptations
- Ensure all team members participate
🟦 Teacher Tip
Substitutions are correct and encouraged. If a team can't find the exact piece, they should use a similar one. This is mathematical problem-solving, not a building test.
🔁 If students struggle…
- If building takes too long: "Freeze your model as is and move to counting."
- If many pieces are missing: "Use similar pieces — that's fine."
- If team is stuck: "Ask another team for help finding pieces."
📝 Teacher Notes
- Brickit recognises shape and size, not colour. Substitutions are expected and correct.
- The model does not need to match the instructions exactly. Approximate matches are fine.
- If building is taking too long, it's acceptable to move to the math part with an incomplete model.
🔍 Mathematical Exploration — First Count (Baseline)
Duration: 7–8 minutes
🧠 Strategy Awareness
You may use different counting strategies. Notice how others work and try new strategies. Strategies are optional; accuracy is the goal.
👩🏫 Instructions
"Choose one strategy and count the bricks in your model. This is your first count."
"You can count by ones, by colours, by identical shapes, or by layers. Choose what helps you stay accurate."
"One student counts, one checks. How do you know you didn't skip a brick?"
👧👦 What You Need to Do
- Choose one counting strategy
- Complete first count
- One student counts, one checks
- Record count on Recording Sheet
👩🏫 Teacher Focus
- Ask: "How do you know you didn't skip a brick?"
- Ask: "Show me how you're checking your count."
- Observe counting strategies used
- Note which strategies seem most accurate
🟦 Teacher Tip
Children may count in different ways. Encourage noticing how others count and choosing the strategy that helps them stay accurate. Strategies are optional — students choose what works for them.
🔁 If students struggle…
- If students skip bricks: "Point to each brick as you count."
- If count seems wrong: "Try counting by colours instead."
- If team is stuck: "One person counts, the other watches and checks."
📝 Teacher Notes
- Possible strategies: count each brick (ones), count by colours, count by identical shapes, count by layers of the build.
- Children may count in different ways (ones, groups of 2, groups of 5). Encourage strategy awareness — noticing how others work and trying new strategies.
- Strategies are optional — students choose what works for them. Accuracy is the goal.
🔍 Mathematical Exploration — Second Count (Verification)
Duration: 8–10 minutes
👩🏫 Instructions
"Now recount using a different strategy. Mathematicians always verify."
"You can count by 2s, start from a different point, count in colour order, or regroup bricks. Choose a different method than your first count."
"Compare both counts. Do they match?"
👧👦 What You Need to Do
- Perform second count using a different strategy
- Compare both counts
- If totals differ, explain the mismatch
- Recount until two strategies give the same total
👩🏫 Teacher Focus
- Ask: "Which strategy was easier?"
- Ask: "Why do the counts match (or not match)?"
- Ask: "What changed in your second method?"
- Support students whose counts don't match — help them find the error
🟦 Teacher Tip
Verification builds mathematical thinking. Students learn that accuracy matters and that different methods should give the same answer.
🔁 If students struggle…
- If counts don't match: "Try counting again. Point to each brick as you count."
- If students use same strategy: "Try a completely different method — count by 2s or start from the other end."
- If still mismatched: "Let's count together step by step."
📝 Teacher Notes
- Possible verification methods: count by 2s, recount starting from a different point, recount in colour order, regroup bricks physically.
- If counts don't match, students should recount until two strategies give the same total. This is part of learning accuracy.
⚖️ Comparison & Reasoning
Duration: 5 minutes
👩🏫 Instructions
Your teacher will write two teams' totals on the board and ask:
- "Did both teams verify correctly?"
- "Which team used two different strategies?"
- "How many more bricks does Team A have than Team B?"
"Use precise vocabulary: recount, verify, total, difference, match."
👧👦 What You Need to Do
- Compare your totals with other teams
- Explain which strategies you used
- Use precise vocabulary: recount, verify, total, difference, match
- Answer comparison questions in complete sentences
👩🏫 Teacher Focus
- Highlight teams that used two different strategies
- Reinforce mathematical vocabulary
- Celebrate accurate verification
🟦 Teacher Tip
Comparison builds number sense. Students see that different teams may have different totals, and that's okay — accuracy matters more than matching others.
🔁 If students struggle…
- If vocabulary is unclear: "Tell me: did you count again? That's called 'recount' or 'verify'."
- If comparison is hard: "Look at the numbers on the board — which is bigger?"
💭 Reflection & Recording
Duration: 5 minutes
👩🏫 Instructions
"Complete your Recording Sheet with all your work."
"What strategy helped you count accurately today?"
"Did you try a new strategy or learn from someone else?"
👧👦 What You Need to Do
- Record first count on Recording Sheet
- Record second count
- Note strategies used
- Mark matching or mismatch
- Write your equation (if applicable)
- Draw your model
- Reflect on counting strategies you used
👩🏫 Teacher Focus
- Collect evidence of learning through Recording Sheets
- Use Observation Checklist to identify students needing extra practice
- Take photos of models if helpful
- Quick interviews: "Tell me about your counting strategies."
🟦 Teacher Tip
Reflection builds metacognition. Students think about their own thinking and learn from others' strategies.
🔁 If students struggle…
- If Recording Sheet is incomplete: "Check your counts and strategies — make sure everything is recorded."
- If reflection is unclear: "Tell me: did you count by ones, twos, or colours?"
🧩 Differentiation
Emerging Learners (Grade 1)
- Count only by ones
- Compare two small totals
- Focus on matching counts
Developing Learners (Grade 2)
- Count using two structured strategies
- Write an equation for the total
- Explain mismatch causes
Advanced Learners (Grade 2–3)
- Count by 2s or 5s
- Rebuild the model with same total using new pieces
- Teach another team a counting strategy
🧮 Assessment Tools
Use during circulation.
| Skill | Observable Behaviour | Check |
|---|---|---|
| Accurate counting | Performs consistent one-to-one counting | ☐ |
| Verification | Uses a second strategy independently | ☐ |
| Error detection | Explains mismatches clearly | ☐ |
| Recording | Completes sheet with correct totals | ☐ |
| Reasoning | Justifies why counts match | ☐ |
| Vocabulary | Uses key terms correctly | ☐ |
| Collaboration | Shares roles effectively | ☐ |
Success indicators:
Student explains how they counted, not only what they counted
Student demonstrates two different counting methods
Student can defend the correctness of the final total
🌿 Extensions & Challenges
Mismatch Detective
Teacher intentionally miscounts a ready model; students identify the error
Same Total, New Model
Rebuild the model using the same number of bricks
Teach a Strategy
Students explain their recount method to another group
Speed vs Accuracy
Count quickly, then quietly recount for precision
📚 Curriculum Alignment
| Framework | Standards |
|---|---|
| Common Core (US) | 1.OA.A.1, 1.OA.C.6, 1.NBT.A.1, MP3 |
| Cambridge Primary (Stage 1–2) | N1.4–N1.7: Counting and checking strategies; N2.1: Compare and verify numbers |
| IB PYP Mathematics | "Verification strengthens mathematical understanding." "Mathematicians describe and justify their thinking." |