Compare ways to protect a model town from flooding

Which design reduces floodwater reaching model homes?

Submit: Designs, repeated test records and a tradeoff-based recommendation.

Related lesson: Earth's Changing Surface

This is a teacher-led extension beyond the short lesson. The task supplies a performance opportunity; completion alone does not certify mastery, full NGSS coverage or state alignment.

Build the idea

Flooding is a natural process that can affect people. Designs can reduce impacts without preventing all flooding. A barrier, a raised structure and a space that temporarily holds water work in different ways. Compare multiple designs against criteria, including what happens to water redirected elsewhere.

Evidence and model inputs

Illustrative tray results under the same water input: no protection — three model homes reached by water; raised platforms — one reached; low barrier — none reached but water redirected to the model road. The counts describe a fictional example and do not validate a real flood-control system.

Keep actual observations, published findings and invented model cases labeled separately. If a source or required equipment is unavailable, pause that part with a teacher; do not invent results.

Materials and preparation

Trays, modeling material, blocks, absorbent towels and small adult-controlled water inputs. Keep electricity and walking areas dry.

Grade-level scope

Use flooding, earthquakes, tsunamis or volcanic eruptions. This unit uses flooding and compares impacts rather than forecasting a real event.

Do the work

1. Create a shallow tray town with a marked water source and fixed home positions. An adult controls small equal water inputs.
2. Choose criteria: keep homes dry, preserve a road and use a limited amount of material.
3. Build at least two different solutions. Reset the tray and test each using the same input and starting conditions.
4. Record which targets are reached and where the water goes.
5. Revise one design to address a tradeoff and retest. Explain why a small model cannot certify real flood safety.

Learner worksheet

Write on paper or type here and print. Entries stay in this page’s memory and are lost when you leave or reload; they are not saved or submitted.

Check your reasoning

1. Which example best protected homes alone?
2. Why track water outside the protected area?
3. Why reset the tray?
4. Can this model approve a real levee?

Teacher review guide

Review the actual deliverable and discuss the reasoning. For each criterion, use 0 when evidence is absent or fundamentally incorrect, 1 when partly supported with a material error or omission, and 2 when accurate, supported and complete for the stated task. Maximum 8 points is a task score, not a proficiency certification. Give feedback and allow revision.

1. Generates at least two designs for the same hazard.
2. Uses consistent test conditions and records impacts.
3. Compares solutions against more than one criterion.
4. Refines a design and explains model limitations.

Sources and standard reference

• Official NGSS 4-ESS3-2 performance expectation — inspect the practice, core idea, crosscutting concept and assessment boundary.

Instructional text and hypothetical cases are original. Linked source readings supply published evidence where specified. Teachers should judge fit with their course and state requirements.