💡 Lesson Overview
In this lesson, students learn to compare and order LEGO® models using clear measurable attributes:
- height (taller/shorter)
- width (wider/narrower)
- number of bricks (more/fewer)
- understand that comparisons may show differences or equality
- supports purposeful decision-making when choosing a model
Students learn that comparisons must be based on one attribute at a time, and that using attributes helps mathematicians describe objects precisely.
This lesson develops:
- mathematical language
- comparative reasoning
- data organisation
- early measurement skills
Aligned with Common Core (1.MD.A, 1.MD.B), Cambridge Primary Stage 1–2, and IB PYP.
🎯 Today's Goal for Students
👩🏫 What to tell your students at the start of the lesson:
"Today we are learning to compare and order our models. We will look at height, width, and number of bricks to see which model is taller, wider, or has more bricks."
💡 This simple statement helps students understand the purpose of the lesson and makes their actions more meaningful and focused.
🎯 Learning Goals
Measurement Foundations
Compare models using attributes: height, width, brick quantity
Describe objects using precise measurement vocabulary
Number Sense
Compare totals (more/fewer)
Order objects from least to most based on chosen attribute
Mathematical Language
Use "attribute", "taller", "shorter", "wider", "more bricks", "fewer bricks"
Reasoning
Explain comparisons using evidence
Justify the ordering of multiple models
Communication
Speak in complete comparative sentences
Agree on an attribute before comparing
🧠 Skills Developed
| Domain | Focus in this Lesson |
|---|---|
| Measurement | using attributes to compare |
| Reasoning | justifying comparisons & orderings |
| Observation | analysing height, width, repeated parts |
| Communication | full-sentence math talk using measurable language |
| Collaboration | negotiating ordering decisions |
| Problem Solving | comparing models with different shapes |
🧰 Teacher Preparation
Materials per team (typically 2–4 students; up to 5–6 if needed)
200–300 LEGO® bricks
1 device with Brickit App for Schools
Student Recording Sheet – Comparing & Ordering
Teacher Observation Checklist
Mini whiteboards or paper
Before class
Write sample attribute-based sentences: "Model A is taller than Model B. The attribute we compared was height." "Model C has more bricks than Model D. The attribute was number." "We ordered models by one attribute: height."
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
Comparing attributes requires real variation, which naturally happens only when children first create their own models.
Buildings created from Brickit scans vary in height, width, and structure — perfect for comparison tasks.
📄 Student Recording Sheet
Print this worksheet for each student or group:
Lesson 1.4 – Comparing and Ordering Models
Name: ______________________ Date: _______________
1. Attribute I compared:
☐ height ☐ width ☐ number of bricks
2. My model has ______ bricks.
3. Attribute comparison:
My model is ______ (taller/shorter/wider) than ______.
My model has ______ more bricks than ______.
4. Ordering (least → most) based on this attribute:
5. _________________
6. _________________
7. _________________
8. Draw your model:
📘 Lesson Flow
🧺 Sort the Pile
Duration: 5–8 minutes
👩🏫 Instructions
"Sort your bricks by an attribute. This will help you build clearly and compare attributes later."
"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 makes sense to you."
"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
- Organise for easy access during building
- If you see a sorting strategy you like, try it
👩🏫 Teacher Focus
- Reinforce: Sorting is mathematical thinking — grouping, comparing, organising
- Accept any reasonable sorting strategy
- Notice which students organise for easy access
🟦 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."
"Pick a model that looks like it will be fun to compare by an attribute — height, width, or number of bricks."
"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
- has interesting attributes to compare (tall, wide, layered, or multi-part)
👧👦 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" with interesting attributes
👩🏫 Teacher Focus
- Encourage models with interesting attributes (tall, wide, layered, multi-part)
- 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. Models with interesting attributes are ideal for this lesson.
🔁 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: 8–10 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."
"As you build, notice which attributes stand out — height, width, number of bricks."
👧👦 What You Need to Do
- Build collaboratively
- Help each other find pieces
- Notice attributes of your model
- Substitute missing pieces with similar shapes/sizes
👩🏫 Teacher Focus
- Ask: "Which attribute of your model stands out?"
- Ask: "What is the tallest part, or are all parts the same height?"
- Ask: "Which direction is it wider, or are several parts equally wide?"
- Ask: "How many bricks do you think it will have?"
- Observe problem-solving strategies
✅ Accept These Correct Answers
- "They are the same height" — if no part is taller
- "Several parts are equally wide" — if no widest part
- "No colour appears the most" — if colours are similar amounts
These answers are correct and support mathematical comparison skills.
🟦 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 comparing."
- 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.
- This sets up attribute-based comparison.
🔍 Mathematical Exploration — Comparing Models Using a Single Attribute
Duration: 8–10 minutes
🧠 Strategy Awareness
You may compare by different attributes (height, width, number). Notice how others compare and try new strategies. Strategies are optional; clear comparison is the goal.
👩🏫 Instructions
Your teacher will gather 2–3 models and explain:
"Mathematicians compare by choosing one attribute at a time. Today, we will compare your models using one attribute."
"Choose one attribute: height, width, or number of bricks. Compare using that attribute only."
👧👦 What You Need to Do
- Choose one attribute (height, width, or number of bricks)
- Compare models using that attribute
- Use full sentences including the attribute
- Examples: "My model is taller by 2 layers." "My model has 12 bricks. Yours has 9 bricks. The attribute is number."
👩🏫 Teacher Focus
- Height: Ask "Which model is taller, or are they the same height? By how many layers?"
- Width: Ask "Which is wider, or are several parts equally wide? How can you tell?"
- Number: Ask students to count and compare: "My model has 12 bricks. Yours has 9 bricks. The attribute is number."
- Ensure students use full sentences including the attribute
🟦 Teacher Tip
One attribute at a time prevents confusion. Students learn that comparing by height is different from comparing by width or number.
🔁 If students struggle…
- If students mix attributes: "Choose just one attribute. Are you comparing height, width, or number?"
- If comparison is unclear: "Use a full sentence: 'My model is taller by ___ layers.'"
- If students can't decide: "Start with height — which model is taller?"
🔍 Mathematical Exploration — Ordering Models by an Attribute
Duration: 5–7 minutes
👩🏫 Instructions
"Before ordering, agree on the attribute. We can only order by one attribute at a time."
"Choose one attribute: height, width, or number of bricks."
"Order 3–4 models from least to most: shortest → tallest, fewest → most, narrowest → widest."
👧👦 What You Need to Do
- Choose one attribute (height, width, or number of bricks)
- Order 3–4 models from least to most
- Label order positions (1st, 2nd, 3rd…)
- Explain your ordering decisions
👩🏫 Teacher Focus
- Ensure students agree on the attribute before ordering
- Support students who struggle to order 3–4 models
- Reinforce: One attribute at a time
- Celebrate clear explanations of ordering decisions
🟦 Teacher Tip
Ordering builds systematic thinking. Students learn to compare multiple items and arrange them logically.
🔁 If students struggle…
- If students mix attributes: "Remember: one attribute at a time. Are you ordering by height, width, or number?"
- If ordering is unclear: "Start with just 2 models. Which is taller? That's 1st. The other is 2nd."
- If students can't decide: "Count the layers or bricks to help you decide."
💭 Reflection & Recording
Duration: 5 minutes
👩🏫 Instructions
"Complete your Recording Sheet with all your work."
"What strategy helped you compare models today?"
"Did you try a new strategy or learn from someone else?"
👧👦 What You Need to Do
- Record attribute used for comparison
- Record comparisons made
- Record ordering (if applicable)
- Record brick counts
- Reflect on comparison strategies you used
👩🏫 Teacher Focus
- Collect evidence of learning through Recording Sheets
- Check vocabulary and reasoning
- Take photos of models if helpful
- Quick interviews: "Tell me about your comparison strategy."
🟦 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 comparisons and ordering — make sure everything is recorded."
- If reflection is unclear: "Tell me: which attribute did you use to compare?"
🧩 Differentiation
Emerging (Grade 1)
- Compare by height
- Use "taller/shorter"
- Order 2–3 models
Developing (Grade 2)
- Compare by number
- Explain "more/fewer" in sentences
Advanced (Grade 2–3)
- Compare by 2 attributes
- Explain how ordering changes when attribute changes
🧮 Assessment Tools
Use during circulation.
| Skill | Observable Behaviour | Check |
|---|---|---|
| Attribute choice | Picks one attribute before comparing | ☐ |
| Height/width comparison | Uses measurable language | ☐ |
| Brick count comparison | Uses "more/fewer" correctly | ☐ |
| Ordering | Orders models by one attribute logically | ☐ |
| Vocabulary | Uses "attribute", "taller", "more bricks" | ☐ |
| Reasoning | Explains comparisons with evidence | ☐ |
| Collaboration | Works cooperatively | ☐ |
Success indicators:
Student chooses an attribute independently
Student uses comparative vocabulary precisely
Student justifies ordering decisions
🌿 Extensions & Challenges
Change the Attribute
Order models by a new attribute and see how the order changes
Difference Questions
"How many layers taller?" "How many more bricks?"
Attribute Hunt
Find hidden attributes in your Brickit model: repeated colours, symmetry, layers
Rebuild Challenge
Rebuild the model to increase one attribute (e.g., "Make it 2 layers taller")
📚 Curriculum Alignment
| Framework | Standards |
|---|---|
| Common Core (US) | 1.MD.A.1 — Compare lengths using attributes; 1.MD.B — Organise and interpret data; 1.OA.A — Compare sets |
| Cambridge Primary (Stage 1–2) | M1.1–M1.3 (compare and order objects); N1.2 (compare sets) |
| IB PYP Mathematics | "Measurement helps compare and order objects using attributes." |