Water for Schools
Menu

Classroom activity Grade 2 Math

Downspout Dash at Harrowgate: A Grade 2 Rain Barrel Board Game

Teams move a token along a roof-to-rain-garden path, drawing cards that add or take gallons, and keep a running barrel total within 100 on a record sheet.

Objectives

  1. Students will apply an add-to or take-from change to a running two-digit total.
  2. Students will record each new total in order on a game sheet.
  3. Students will find how many more gallons would fill a barrel of a stated size.

Vocabulary

Downspout
A downspout is the pipe that carries rainwater down from a roof's gutters to the ground. Where that water goes next, whether onto a lawn, into a rain barrel, or straight to a storm drain, makes a big difference in how much runoff a property sends downstream.
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: gutter, total, overflow

Teacher overview

Groups of four play a short board game along an eight-space path that runs from a roof to a rain garden at a house in the town of Harrowgate, drawing a card at each space that either adds gallons from a storm or takes gallons out for watering. The running total on the record sheet is the water standing in the barrel, and the path follows, space by space, the route roof water actually takes. The misconception the game is built to correct is the habit of adding the two most recent numbers instead of applying the change to the current total, which shows up as a student writing 67 after a take-15 card lands on a total of 52. Require the current total to be read aloud before the card is applied.

Activity Directions

  1. Before class, print one path sheet per group. The eight spaces are labeled roof, gutter, downspout, barrel, overflow pipe, splash block, swale, and rain garden, in that order.
  2. Print and cut the card deck. Half the cards read "storm adds" with a two-digit number, and half read "watering takes" with a two-digit number. Keep every number under 30, and stack the two kinds so that storm and watering cards alternate through the deck. If a watering card is larger than the total in the barrel, the barrel empties to zero and the turn ends there.
  3. Seat students in groups of four and give each group a path, a deck, a token, and one record sheet per player. Explain that the barrel in the town of Harrowgate holds 75 gallons when it is full, and that the group starts with 34 gallons already in it.
  4. Play in turns. The player moves the token forward one space, draws a card, reads the current total aloud, and then says the new total. Every player writes the new total on their own record sheet, so all four students do the arithmetic on every turn.
  5. The group checks the new total together. If two players disagree, they settle it on a hundred chart before the next turn. When a storm card would carry the total past 75 gallons, the barrel stops at 75 and the group writes the leftover gallons in the overflow column, which is the water that runs on to the rain garden.
  6. The game ends when the token reaches the rain garden space, which happens after eight turns. Groups that finish early reshuffle and play a second round starting from their final total.
  7. Hand out the recording page and give students 10 minutes to answer the six questions on their own.
  8. Close with a two-question debrief: ask what happened to the total on a watering card and why, and ask where the water goes once the barrel is full and the overflow pipe carries it away.
Downspout Dash at Harrowgate: A Grade 2 Rain Barrel Board Game — Grade 2 Math
Name: ____________________________ Date: ______________

Student Handout

Imagine your group is playing Downspout Dash at the house in the town of Harrowgate. The barrel holds 75 gallons when it is full. Answer the questions in order.

  1. The barrel starts with 34 gallons. A storm card adds 18 gallons. What is the new total?
  2. The barrel has 52 gallons. A watering card takes 15 gallons. What is the new total?
  3. The barrel has 37 gallons. A storm card adds 26 gallons. What is the new total?
  4. The barrel has 63 gallons. A watering card takes 9 gallons. What is the new total?
  5. The barrel holds 75 gallons when full. It has 54 gallons in it now. How many more gallons would fill it?
  6. The barrel started with 34 gallons and ended with 54 gallons. How many more gallons were in the barrel at the end?

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: 52 gallons. Add the storm card to the starting total: 34 + 18 = 52.
  2. Answer: 37 gallons. Take the watering card from the current total: 52 - 15 = 37. A student who answers 67 has added instead of subtracting.
  3. Answer: 63 gallons. Add the storm card to the current total: 37 + 26 = 63.
  4. Answer: 54 gallons. Take the watering card from the current total: 63 - 9 = 54.
  5. Answer: 21 gallons. Subtract what is in the barrel from what it holds: 75 - 54 = 21.
  6. Answer: 20 gallons. Compare the last total with the first: 54 - 34 = 20.

Differentiation

Support

Give these students a record sheet with the current total already printed on each line so they only write the new total, and hand their group a deck with every number under 15. A hundred chart and a set of ten sticks and ones cubes let them model each move before writing it.

Extension

Ask these students to design four new cards, two that add and two that take, so that a game starting at 34 gallons ends exactly at 75 gallons, and to show the four number sentences that prove it. A further challenge is to explain what the group should do if a storm card would push the total past 75 gallons.

ELL supports

Walk the class along the eight path labels with a photograph or a simple drawing for each one before play begins, since gutter, downspout, splash block, and swale are unlikely to be familiar. Post two sentence frames beside the board: "The storm adds ___ gallons," and "The watering takes ___ gallons."

Extensions

Have each group play a second version in which the barrel in the town of Harrowgate holds 100 gallons instead of 75 gallons, and ask students to predict before playing whether the barrel will overflow. Comparing the two barrel sizes with the same card deck gives a concrete reason to talk about why a bigger barrel keeps more roof water out of the street.