Classroom activity Grade 4 Engineering & Design
Marlowbend's Storm Day: A Stormwater Placement Game
A grade 4 team game in which students spend a fixed credit budget placing rain gardens, barrels, and porous pavement on a town grid to keep two low corners dry.
Objectives
- Students will place stormwater pieces on a town map within a fixed credit budget.
- Students will predict how many water cubes reach a low corner during each storm.
- Students will compare their plan with another team's plan and name one change to make.
Vocabulary
- Rain garden
- A rain garden is a shallow planted dip in the ground that catches rain running off a roof or driveway and lets it soak slowly into the soil. Its deep-rooted plants help clean the water.
- Rain barrel
- A rain barrel is a container that catches rainwater from a roof downspout so it can be used later to water plants. It saves drinking water and keeps some runoff out of the storm drains.
Also: porous pavement, budget, flood
Teacher overview
This is a tabletop placement game for teams of three, played on a printed four-by-four map of Marlowbend, a town invented for this activity. Water cubes fall on the hilltop row and move down one row per turn, staying in their own column, and every stormwater piece a team buys removes cubes from the column it sits in. The game teaches that stormwater work is a placement decision made under a spending limit rather than a matter of building as much as possible, because the same three pieces do a great deal of good in one column and nothing at all in another. Plan on 50 minutes, including a gallery walk in which teams compare plans.
Activity Directions
Before class (10 minutes of prep). Print one town map per team and cut enough paper squares for pieces. Each team needs about 15 counters to stand in for water cubes. Groups of three work best, with one student moving cubes, one tracking the budget, and one recording results.
Set the scene (5 minutes). Tell the class that Marlowbend's library door and bus loop both flood in heavy rain. Point out on the map that the ground slopes from row 1 down to row 4, so water travels down its own column and never moves sideways. Show that column B ends at the library door and column D ends at the bus loop.
State the rules and the limit (5 minutes). Read the two targets aloud: no more than 2 water cubes may reach the library door in any one storm, and no more than 2 may reach the bus loop. Then read the limit: each team may spend 12 build credits or fewer. Have each team copy both targets and the limit onto the top of its plan sheet before touching a single piece. Teams that skip this step almost always overspend.
Buy and place (10 minutes). Teams pick pieces from the menu on the handout and set them on legal squares. A rain barrel only fits a roof square, porous pavement only fits a gray square, and a rain garden only fits a lawn square. Teams write each purchase and its cost on the plan sheet and total the credits. Walk the room and ask one question at each table: which column is that piece protecting?
Run the three storms (10 minutes). Read Storm 1 aloud. Teams place the listed cubes on the named row 1 squares, then move every cube down one row at a time. When a cube enters a square holding a piece, that piece absorbs it until the piece is full. Cubes that survive to row 4 land on the corner. Record how many reached the library door and how many reached the bus loop, then empty every piece and run Storm 2 and Storm 3 the same way.
Score (5 minutes). A plan succeeds when both corners stayed at 2 cubes or fewer in all three storms and the team spent 12 credits or fewer. Have each team mark its plan as a success or a miss and write the credits it actually spent.
Gallery walk and debrief (5 minutes). Teams leave their maps and plan sheets on the desks and walk to two other tables. Close with two questions put to the whole class: which single square turned out to be worth the most, and did any team find a plan that worked for fewer credits than yours? Then ask what a team would change if the town cut the budget to 8 credits.
Student Handout
The Marlowbend town map
Water falls on row 1 and moves down to row 4. It stays in its own column.
| Column A | Column B | Column C | Column D | |
|---|---|---|---|---|
| Row 1 (hilltop) | roof | roof | roof | parking (gray) |
| Row 2 | lawn | parking (gray) | lawn | lawn |
| Row 3 | lawn | street (gray) | street (gray) | lawn |
| Row 4 (bottom) | grass edge | LIBRARY DOOR | grass edge | BUS LOOP |
Piece menu
| Piece | Cost in build credits | Cubes it holds | Squares it may sit on |
|---|---|---|---|
| Rain barrel | 2 | 2 | roof squares only |
| Rain garden | 3 | 3 | lawn squares only |
| Porous pavement | 4 | 4 | gray squares only |
Storm cards
| Storm | Cubes on B1 | Cubes on C1 | Cubes on D1 |
|---|---|---|---|
| Storm 1 | 3 | 0 | 3 |
| Storm 2 | 4 | 2 | 2 |
| Storm 3 | 5 | 0 | 4 |
Your targets and your limit
- No more than 2 cubes may reach the library door in any one storm.
- No more than 2 cubes may reach the bus loop in any one storm.
- Your team may spend 12 build credits or fewer.
Questions
- Suppose a team builds nothing at all. In Storm 3, how many cubes reach the library door?
- Suppose a team builds nothing at all. In Storm 3, how many cubes reach the bus loop?
- A team puts one porous pavement piece on square B2 and nothing else in column B. In Storm 3, how many cubes reach the library door?
- Write the squares your team chose and the total credits your team spent.
- After all three storms, did your plan meet both targets? Give the largest number of cubes that reached either corner.
- Name one piece your team bought that never caught a single cube, or write "none" if every piece caught at least one. Explain why that happened.
- Your team gets one change before a fourth storm. Name the square you would change and say what you expect it to do.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
- Answer: 5 cubes.
Storm 3 drops 5 cubes on B1. With nothing in column B, all 5 travel down to the library door, which is 3 more than the target allows. - Answer: 4 cubes.
Storm 3 drops 4 cubes on D1, and with nothing in column D all 4 reach the bus loop. - Answer: 1 cube.
Porous pavement holds 4 cubes. Storm 3 sends 5 cubes down column B, so the pavement absorbs 4 and 1 continues to the library door. One cube is inside the target of 2. - Answer: Accept any legal plan costing 12 credits or fewer, with each piece on a square its menu row allows and the costs totaled correctly.
- Answer: Accept the team's own recorded number, checked against its map. A plan meets both targets only when the largest count at either corner across all three storms is 2 or fewer.
- Answer: Accept any honest answer. Look for the explanation rather than the piece. The usual cause is a piece placed in column A, where no storm card sends cubes, so the credits bought nothing. A piece in column C catches cubes only in Storm 2, and column C ends at a grass edge, so it protects neither corner.
- Answer: Accept any named square with a stated expectation. Strong answers move credits out of column A or C and into column B, the column carrying the heaviest storm load, or trade one expensive piece for two cheaper ones that cover both threatened columns.
Differentiation
Support
Run Storm 1 together as a whole class on a projected map before teams buy anything, so the movement rule is clear before the budget decision arrives. Give these teams a plan sheet with the credit column already set up as a running total, and limit the menu to rain gardens and porous pavement so the roof rule does not add a third thing to track.
Extension
After the gallery walk, ask these teams to find the cheapest plan that still meets both targets in all three storms, and to prove it by listing one plan that costs one credit less and showing which storm breaks it. Then hand them a fourth storm card of their own design that would defeat their winning plan, and ask what they would add.
ELL supports
Label the map squares with small pictures as well as words, showing a roof, a parking lot, a patch of grass, and a doorway. Demonstrate the absorb rule physically by covering a square with a paper piece and sliding cubes under it until it is full. Provide the sentence frames "I put a ____ on square ____ because ____." and "In Storm ____, ____ cubes reached the ____."
Extensions
Bring the game outdoors and walk the class to the lowest spot on the school grounds after a rain, tracing with chalk or flags the path water took to get there. Ask which of the three game pieces could actually go on that path, which could not, and what a real crew would have to check before building anything, such as where the buried pipes run and who owns the ground.