Learning Targets

Standard: CCSS 6.G.A.1 Time: ~40 min Materials: This activity (device or printed), scratch paper Grade 6
Teacher Notes (not printed)

Pacing

  • Launch (5 min): Read "The Brief" together. Anchor the scale: "1 grid square = 1 meter." Model reading the roof's base and height off the blueprint.
  • Design work (25–30 min): Students complete Task 1 → 4 in order. Task 4 (Budget Board) requires Tasks 1–3 results, so encourage them to check each surface as they go.
  • Debrief (5–10 min): Discuss the Level 2 budget inequality and the decompose-vs-compose strategies for the L-shaped plaza.

Differentiation

  • Level 1 (support): Use the green callouts and bilingual (EN/ES) prompts. Provide a printed formula card. Let students draw the decomposition lines on the L-shape before computing.
  • Level 2 (enrichment): Have students prove the plaza area two ways (decompose vs. compose) and solve the budget inequality 38000 + 2376 + 5040 + 135p ≤ 60000 for the affordable material price p.

STEM Connection

  • This is a true engineering design task: Define → Measure → Calculate → Estimate → Decide. Students apply area math the way an architect or civil engineer does — scale plans, material take-offs, and budget constraints.
Unit 5 · Math Architect · Area (6.G.A.1)

Design Challenge: The Riverside Pavilion Park

You are the lead architect for Bayside Parks. The city wants a riverfront park built around a triangular shade pavilion. Use scale drawings and area math to plan every surface, choose materials, estimate the cost, and bring the build in under $60,000.

Standard 6.G.A.1 Composite Area Scale Drawings STEM Design Cycle Budget Engineering
1 · DefineRead the brief & constraints (budget, scale).
2 · MeasureRead dimensions off each scale blueprint.
3 · CalculateFind composite areas with area formulas.
4 · EstimateTurn area into material cost.
5 · DecideAdjust materials to meet the budget.
Surfaces approved: 0 / 6

The Brief

The city handed you a scaled site plan. Every blueprint on this page uses the same scale:

SCALE  1 grid square = 1 meter  ·  site plan drawn to scale

Deliverable 1
Compute the area of each surface from its scale drawing.
Deliverable 2
Choose materials & compute cost per surface.
Deliverable 3
Keep the total build under $60,000.
Level 1 · Support

Area is how much flat surface a shape covers, measured in square meters (m²). For a tricky shape, cut it into rectangles and triangles you know, find each area, then add them up.

Español: El área es la superficie plana que cubre una figura, medida en metros cuadrados (m²). Para una figura difícil, córtala en rectángulos y triángulos, halla cada área y súmalas.

Architect's Formula Toolkit

b (base) h (height)
RectangleA = b × h
b (base) h
TriangleA = ½ × b × h
b₁ top b₂ bottom
TrapezoidA = ½(b₁+b₂)×h

Composite strategy — Decompose (cut the shape into pieces) or Compose (frame a big rectangle, then subtract the missing corner). Both give the same area; pick the one with fewer steps.

Task 1 · The Shade Pavilion Roof Triangle

The signature pavilion has a triangular fabric roof. Read its dimensions off the scale blueprint, then size and price the shade fabric.

base = 18 m h = 12 m Fabric Roof
Plan view · Pavilion roof1 square = 1 m

Q1.1 — Area of the triangular roof

Q1.2 — Shade fabric costs $22 / m². What is the fabric cost?

$

Level 1 · Support

Triangle area = ½ × base × height. Multiply the two numbers, then take half. Cost = area × price per m².

Español: Área del triángulo = ½ × base × altura. Costo = área × precio por m².

Task 2 · The Entry Plaza Composite figure

The paved entry plaza is an L-shape. Decompose it into two rectangles, find each area, then add. The colored regions on the blueprint show the cuts.

16 m 12 m notch 8 m A B
Region A = 8 × 6 · Region B = 16 × 61 square = 1 m

Q2.1 — Area of Region A (upper-left, 8 m × 6 m)

Q2.2 — Area of Region B (bottom strip, 16 m × 6 m)

Q2.3 — Total plaza area (A + B)

Level 1 · Support

An L-shape splits cleanly into two rectangles. Area of a rectangle = length × width. Add the two rectangle areas for the total.

Español: Una forma de L se divide en dos rectángulos. Área = largo × ancho. Suma las dos áreas para el total.
Level 2 · Enrichment

Prove it two ways. Decompose: region A + region B. Now compose: frame the whole 16 × 12 rectangle and subtract the missing corner. Do you get the same answer? Which method used fewer steps here, and why?

Task 3 · The Riverbank Garden Trapezoid

The garden follows the curve of the river, so it is shaped like a trapezoid. Find its area, choose a ground cover, and watch the live cost update.

top b₁ = 10 m bottom b₂ = 20 m h = 9 m Garden
Plan view · Riverbank garden1 square = 1 m

Q3.1 — Area of the trapezoidal garden

Choose a ground cover

Selected
Area
135 m²
Garden cost
$0

Live cost = 135 m² × price/m². This feeds straight into your Budget Board in Task 4.

Task 4 · Final Budget Board Estimate & decide

Bring it together. Enter the roof and plaza costs you computed; the garden cost auto-fills from your material choice. Then tally the build against the $60,000 budget.

Surface Area (m²) Your cost ($)
Pavilion roof — fabric @ $22/m² 108
Entry plaza — paving @ $35/m² 144
Riverbank garden — your material 135
Site labor — fixed
Total estimate $0

Plaza paving cost = 144 m² × $35. Compute it and enter it to confirm you can turn area into money.

Budget
$60,000
Remaining

Level 1 · Support

Total = roof + plaza + garden + labor. Remaining = budget − total. Positive remaining = under budget (good). Negative = pick a cheaper material.

Español: Total = techo + plaza + jardín + mano de obra. Restante = presupuesto − total. Si el restante es positivo, estás dentro del presupuesto.
Level 2 · Enrichment

If river-stone ($20/m²) pushes you over budget, what is the highest garden material price p you can still afford? Using your computed roof cost, plaza cost, garden area, and the $38,000 labor, write and solve:

labor + roof cost + plaza cost + 135·p ≤ 60,000

Architect's Sign-off

When every surface checks out and your plan is under budget, submit it to the city council. Enter your name in the field below, then press Submit plan & grade to save your score as a PDF or DOC.

Performance Rubric — Area Design Challenge (6.G.A.1)

Level Score Descriptor
4 — Exceeds 6 / 6 Reads every scale drawing accurately and applies triangle, composite, and trapezoid area formulas correctly. Brings the build under budget and can explain the decompose/compose strategies and the budget inequality.
3 — Meets 5 / 6 Correctly computes most surface areas and costs with at most one arithmetic slip. Completes the budget board and reaches a valid under-budget plan.
2 — Approaching 3–4 / 6 Computes simple areas but struggles with the composite figure or trapezoid (e.g., forgets to halve, or does not add both bases). Partial cost/budget work.
1 — Beginning 0–2 / 6 Few correct areas. Confuses formulas or misreads the scale. Needs reteaching on area formulas and reading scale drawings.