1.1 Small Group · Group 2
Tier 1 Extension · Non-Routine Synthesis · Misconception Traps · Rigorous CER Proofs
doer of math · math story · Procedural Fluency · Real-World Applications
- You already can do this. So we go up a level, not up a number: find what is always true, show it a second way, and be ready to defend it with a reason instead of an answer.
- The Ferris wheel has 20 cars, and about 4 people fit in each car. About how many people can ride at one time?
- I count the cars: 20. Then I estimate how many riders fit in one car: about 4.
- I do not count every person — an estimate is a reasoned answer that is close enough to be useful.
- 20 × 4 = 80, so I would say “about 80 people.”
- 5 = 70 + 8.5.
- 5 = 78 + 0.5.
- 5 = 80 − 1.5.
- Every one of those is the same number wearing different clothes. Find two more.
- Now prove it: say why that move had to work at all — not just that it did.
- Sentence frame — convince a skeptic: "My method works because ___ . It would stop working if ___ ."
- doer of math (persona que hace matemáticas) — Anyone who uses mathematical thinking — which is everyone, every day.
- math story (historia matemática) — Your own history with mathematics — what you have done, felt, and learned so far.
- strength (fortaleza) — Something you already do well and can share with others.
- decompose (descomponer) — To break a number into parts that add, subtract, multiply, or divide back to it.
- estimate (estimar) — A reasoned answer that is close enough to be useful, without counting every one.
- Believing that 'doing math' only counts when it happens on paper in a classroom.
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1 FILL TABLE
Use mental math to complete each Ferris wheel estimate.
Situation Estimate Answer 20 cars, each holding about 4 riders About 80 riders each turn, 6 turns in an hour About 480 riders each hour, for 2 hours ✏️ Scratchpad / Reasoning -
2 MATCHING GAME
Match each number to a correct decomposition.
- 78.5
- 78.5 using multiplication
- 480
- 12.5
- A70 + 8 + 0.5
- B(7 × 10) + (8 × 1) + (5 × 0.1)
- C6 × 80
- D12 + 0.5
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3 MULTIPLE CHOICE
Estimating 23 × 4, Sam rounds 23 to 20. Nia instead splits it: 23 × 4 = (20 × 4) + (3 × 4). Which comparison is accurate?
- ASam's is faster but loses 12 riders; Nia's takes one more step and lands exactly on 92
- BBoth give exactly 92, so there is no difference between them
- CNia's is an estimate too, because she broke the number apart
- DSam's is the only real estimate, so Nia's method does not count
✏️ Workspace & Solution Steps -
4 MULTIPLE CHOICE
The operator removes 3 cars for repairs, so the 23-car wheel now runs 20 cars, and adds a fifth seat to every car. Without multiplying it out, what happens to the number of riders in one turn?
- AIt goes up — losing 3 cars costs about 12 riders, but a fifth seat in 20 cars adds 20
- BIt stays the same — one change up and one change down cancel out
- CIt goes down — removing cars always matters more than adding seats
- DThere is no way to tell without doing the multiplication
✏️ Workspace & Solution Steps
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5 OPEN RESPONSE
At the same fair, a food stand sells about 38 drinks an hour and is open 7 hours. Estimate the drinks sold in a day, using a strategy of your choice. Then describe a DIFFERENT strategy a classmate could reasonably use, and say what each one is better for.
✏️ Mathematical Justification & Response -
6 OPEN RESPONSE
Ask a classmate about their math story. What is one way their story is DIFFERENT from yours?
✏️ Mathematical Justification & Response
Complete each sentence stem to demonstrate precise mathematical reasoning:
Writing Task: Justify why your mathematical solution is accurate and complete.