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Lesson plan Grade 3 Engineering & Design

Ferngate Flood Barrier: A Grade 3 Model Levee Design

A grade 3 engineering lesson where students build and test a clay-and-stick levee to keep model Ferngate dry when Otter Run floods, then judge the design.

Objectives

  1. Students will define a flood problem with a clear success criterion and stated material limits.
  2. Students will build and test a model levee that reduces flooding in a tray town.
  3. Students will make a claim about whether their levee is worth building, using their test results.

Vocabulary

Levee
A long earthen wall built along a river to keep floodwater out of the nearby land. Levees protect many towns, but they can fail if water rises too high.

Also: flood, barrier, criteria, constraint

Teacher overview

Ferngate is a small tray town that sits beside a creek called Otter Run. When heavy rain fills the creek, water spills over the bank and soaks the houses. In this lesson, groups take on the job a real stormwater engineer does: they define the problem, build a low wall called a levee from a fixed set of materials, and run a fair test to see whether their wall keeps the model houses dry. Success is judged by watching where the water goes rather than by computing a number, and the closing discussion turns on whether the test results support building the barrier at all.

Procedure

Hook (5 min): Set up one tray town in front of the class: place three small blocks as houses on one side and pour a cup of water along the far edge to act as Otter Run. Tip the tray slightly and let students watch the water reach the houses. Ask, "How could we keep these houses dry the next time it rains hard?"

Define the problem (8 min): Write the success criterion on the board with the class: every house stays dry after one full cup of water is poured. Then list the constraints together: each group gets only one lump of clay, ten craft sticks, and a few sponge pieces, and has fifteen minutes to build. Name this the design problem, and point out that real engineers always work inside limits like these.

Plan (7 min): Each group sketches one levee idea on scrap paper before touching materials. The sketch must show where the wall sits between the creek and the houses and how tall it will be. Circulate and ask each group to point to the part of their plan that meets the "dry houses" criterion.

Build (15 min): Groups build their levee in the tray using only the listed materials. Remind them that clay can seal gaps where water sneaks through and that craft sticks can hold a wall upright. Keep the toy houses in place so the wall is built to protect them.

Fair test (10 min): Each group pours exactly one full cup of water along the creek edge, the same amount for everyone, so the test is fair. Groups watch whether water reaches the houses and mark on their handout whether each house stayed dry or got wet.

Claim and debrief (10 min): Groups complete the handout and share one claim: is their levee worth building? For a quick formative check, ask for a thumbs-up from every student who can state one piece of evidence from their own test; if fewer than half can, model one evidence sentence aloud before dismissal.

Ferngate Flood Barrier: A Grade 3 Model Levee Design — Grade 3 Engineering & Design
Name: ____________________________ Date: ______________

Student Handout

Answer each question about your own group's levee test.

  1. What was the success criterion your levee had to meet?
  2. After you poured one cup of water, how many of your houses stayed dry?
  3. Name one material that helped your wall hold back the water, and tell what it did.
  4. Where did water get through, if it did? What would you change to fix that spot?
  5. Make a claim: is your levee worth building for Ferngate? Give one piece of evidence from your test.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: Every house had to stay dry after one full cup of water was poured. Accept any restatement naming dry houses as the goal.
  2. Answer: A number from 0 to 3 that matches what the group actually observed; this is a recorded observation, not a fixed value, so accept the group's honest count.
  3. Answer: Accept clay (seals gaps so water cannot pass), craft sticks (hold the wall up and make it taller), or sponge (soaks up water) with a matching explanation of what the material did.
  4. Answer: Accept any answer that names a real leak point the group saw, such as a gap at the end of the wall or a spot that was too low, plus a sensible fix like adding clay or building higher.
  5. Answer: Accept either a yes or a no claim as long as it is backed by the group's own evidence, such as "Yes, because all three houses stayed dry" or "No, because water leaked past the left end and two houses got wet."

Differentiation

Support

Give these groups a pre-drawn tray map showing exactly where the creek and houses sit, so planning time goes toward the wall itself. Pre-roll the clay into a long rope so the building step starts faster, and pair the group with an adult who can ask, "Where might water still get through?"

Extension

Challenge these groups to protect the houses against two cups of water instead of one, then compare which parts of their first design failed under the larger flood. Ask them to redraw their plan and name the one change that made the biggest difference.

ELL supports

Pre-teach "levee," "flood," and "barrier" with a labeled picture of a real river levee. Provide sentence frames for the claim on the handout: "My levee ___ worth building because ___." Allow students to label a diagram of their tray instead of writing full sentences for questions 3 and 4.

Extensions

Invite the class to look at photos of real levees or sandbag walls along a river and name the same parts they built in miniature. If your city has a public works or stormwater department, a short class letter asking how the town protects homes from flooding turns this model into local knowledge.