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Lesson plan Grade 5 Engineering & Design

Fenwick's Wren Creek Dam: A Grade 5 Build-and-Improve Challenge

A grade 5 engineering design challenge where teams build a model dam across Wren Creek, test it for leaks, then improve one feature at a time in a fair second round.

Objectives

  1. Students will build a model dam that holds back water and identify where it leaks or fails.
  2. Students will compare two dam designs and explain which one better meets the success criteria.
  3. Students will improve their dam after a fair test by changing one feature at a time.

Vocabulary

Dam
A strong wall built across a river to hold back water. Dams store water for people and farms, help prevent floods, and can make electricity.
Reservoir
A human-made lake, usually created by a dam, that stores water for later. Reservoirs supply cities and farms and help control floods.
Spillway
A dam's overflow channel, giving extra water a safe path around or over the dam when the reservoir gets too full. It protects the dam from being damaged in floods.

Also: leak, prototype, failure point

Teacher overview

Fenwick is a fictional town that wants to hold back the spring flow of Wren Creek so it has water for the dry months. Holding water back takes a dam, and a dam must do two jobs at once: keep the reservoir behind it from leaking away, and let extra water pass safely over a spillway so the dam does not wash out. In this challenge, teams build a model dam across a tray "creek," test it, find where it leaks, and then improve one feature in a fair second round. The lesson does not produce a single right answer; each team's results depend on their own build, so the focus is on testing carefully and improving from what they observe.

Procedure

Hook (5 min): Raise one end of a tray on a book and pour a cup of water at the top so it runs down. Ask students how they could stop that water partway and make a small pond. Take a few ideas.

Frame the design problem (10 min): Set the success criteria on the board: the dam must hold a full measuring cup of water behind it for 30 seconds without the reservoir draining, and it must let extra water pass over a spillway without the dam collapsing. Set the constraints: teams may use only the materials on the table, the tray stays raised on the same single book for every test, and every team pours the same amount of water so the test is fair. Explain that clay, sticks, and stones each behave differently, and part of the job is choosing well.

Build round 1 (15 min): In teams of three or four, students build a first dam across the middle of the tray. Remind them to plan a low spot, a spillway, where extra water can escape on purpose instead of breaking through somewhere else.

Test and formative check (5 min): Each team pours one measuring cup of water above the dam and times how long the reservoir holds. Do a thumbs-up poll: thumbs up if the dam held water for the full 30 seconds. If fewer than half of teams held water, pause and list on the board the two most common leak spots you saw, so every team has an idea to try.

Plan the improvement (5 min): Each team decides on one feature to change for round 2, such as packing the clay base tighter or lowering the spillway. Stress that they change only one feature, so they can tell whether that change is what helped.

Build, test round 2 (15 min): Teams rebuild with their one change and pour the same measuring cup of water again, timing the hold. They note whether the change made the dam hold better, worse, or about the same.

Debrief (5 min): Ask two questions to the whole class. First: "Where did most dams leak, and why do you think that spot failed?" Second: "Did changing only one feature make it easier or harder to tell what helped? Explain." Call on several teams so different results are heard.

Fenwick's Wren Creek Dam: A Grade 5 Build-and-Improve Challenge — Grade 5 Engineering & Design
Name: ____________________________ Date: ______________

Student Handout

Use this design log during the challenge. You do not need full sentences; short notes and labeled sketches are fine.

  • Sketch your round 1 dam. Label the spillway and the reservoir.
  • After the test, mark with an X where your dam leaked or failed.
  • Write the one feature you will change for round 2, and why.
  • Sketch your round 2 dam and mark whether it held better, worse, or about the same.
  • Write one sentence: which design met the criteria better, and how do you know?

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

Differentiation

Support

Give these teams a tray with the spillway spot already marked and a starter ridge of clay in place, so they begin from a partly built dam. Pair students so one shapes clay while the other pours and times, and provide a checklist of the two criteria to look at during each test.

Extension

Challenge these teams to add a second job: after holding water, open a small gate in the dam and route the released water to spin a paper pinwheel "waterwheel" placed below. Have them explain how a real dam can both store water and make hydropower, and what trade-off they noticed between holding water and releasing it.

ELL supports

Pre-teach "dam," "reservoir," "spillway," and "leak" using the actual tray and clay as you say each word. Provide a labeled diagram of a dam with the spillway and reservoir marked, and allow students to record their design log with sketches and single words rather than full sentences.

Extensions

Show students photographs of a real dam and its spillway and ask them to find the same parts they built in their models. If a local reservoir, flood-control dam, or hydropower dam is nearby, a class letter to the operating agency asking how the spillway is designed to handle a big storm can turn this challenge into a study of a real structure in their own watershed.