Build Day
Build Day: The Finished Clubhouse
Saturday, and the model clubhouse stands finished on the Blueprint Table. Rocket lifts the cone roof on.
"Roof radius 6, height 8," Raven reads from the Blueprint Book. "What do you notice about its volume?"
"One third of 3.14 times 36 times 8," Rocket says. "301.44 cubic centimeters. The can tank holds 282.6."
He sets the rubber ball by the door. "Radius 3. Four thirds of 3.14 times 27. 113.04."
Raven loops string lights around the roof edge. "Circumference: 2 × 3.14 × 6. About 37.68 centimeters of lights."
Nova hovers above it all, her light soft on the roof. "Twelve weeks, one clubhouse," she says. "Show someone."
Rocket grins. "Floor plan, brace, roof. One measurement from each." Nova hums. "Build Day. Begin."
- Area by composing and decomposing: parallelograms, triangles, trapezoids and any polygon.
- Polygons on the coordinate grid, nets and surface area, and volume with fractional edges.
- Scale drawings, triangles from three measures, slices of solids, and circles with π as 3.14.
- Angle pairs, triangle sums, parallel lines cut by a third, and slides, flips and turns.
- Dilations and similar figures, the Pythagorean theorem and its converse, distances on the grid.
- Round solids: cylinder πr²h, cone one third of that, sphere 4/3 πr³. Irrational numbers like √2 and π.
The finished model: cone roof 301.44 cubic cm, can tank 282.6 cubic cm, ball 113.04 cubic cm.
The string lights go once around the roof edge: 37.68 cm. Every number came from the crew's own tape measure.
| Part | Measurements (cm) | Volume or length |
|---|---|---|
| Cone roof | r 6, h 8 | 301.44 cubic cm |
| Can tank | r 3, h 10 | 282.6 cubic cm |
| Ball | r 3 | 113.04 cubic cm |
| String lights | around a circle of r 6 | 37.68 cm |
Explain one measurement from each: an area from the plan, the brace length, and a volume from the model.
Let your visitor pick any part and ask how you measured it. Show the page in your Blueprint Book.
Finish by saying which week's math you would use first if you built it again.
Ask them to explain one volume from today and why the cone is one third of the can. Pouring rice is the proof.
Cans have smooth rolled rims, rice stays over a tray, and the flashlight never points at eyes.
String lights for the model are string or paper only, never anything electrical.
- Read the question.
- Tap your answer.
The cone roof has radius 6 cm and height 8 cm. What is its volume in cubic centimeters? (Use 3.14 for π.)
The can tank has radius 3 cm and height 10 cm. What is its volume in cubic centimeters? (Use 3.14 for π.)
The ball has radius 3 cm. What is its volume in cubic centimeters? (Use 3.14 for π.)
The string lights go once around the roof edge, a circle of radius 6 cm. How long are they, in cm? (Use 3.14 for π.)