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Lesson plan Grade 2 Social Studies & Civics

Two Days Without a Tap at Marigold Park School

A 45-minute grade 2 economics lesson in which a fictional school loses tap water for two days and students plan and track 80 stored gallons within 100.

Objectives

  1. Students will explain why a school with limited stored water must choose which uses come first.
  2. Students will rank four school water uses and give a reason for the top choice.
  3. Students will add and subtract gallon amounts within 100 to track a stored supply.

Vocabulary

Key words: gallon, store, shut off, choice, first

Teacher overview

A crew has to shut the water off under Marigold Park School for two days to replace a cracked pipe, so the school fills jugs ahead of time and lives on what it stored. Scarcity stays an abstract word for second graders unless the supply is a number they can watch go down, which is what the stored gallon count gives them here. Students rank four school uses, then track the stored gallons across the two days on the handout. The misconception worth naming out loud is that having less water means doing without everything, when in practice a smaller supply changes the order in which things get done.

Procedure

Open with the jug (5 min): Hold up the empty 5-gallon jug. Read aloud: "This jug holds 5 gallons of water. Marigold Park School filled 16 jugs. That is 80 gallons. On Monday and Tuesday no water will come out of the taps, because a crew is fixing a broken pipe under the playground." Ask students to guess out loud whether 80 gallons sounds like a lot, and take three answers without correcting any of them.

Sort the uses (12 min): Write four school water uses on chart paper: drinking, washing hands, cooking lunch, watering the garden. In table groups, students decide which use should get water first and which could wait until Wednesday. Each group reports its top choice and one reason. Record the reasons next to each use. Name the idea plainly: when there is not enough for everything, people have to choose an order.

Model the tracking (13 min): On the board, walk through one running total together. Start at 80 gallons, take away 25 for the kitchen, and land on 55. Show the subtraction two ways, once with a number line and once by counting back by tens. Then take away 20 more for hand washing and land on 35. Ask a student to explain in their own words what the 35 stands for.

Handout (10 min): Students complete the five problems on their own. Items 1 and 2 repeat the two steps modeled on the board, so watch that students are writing the reasoning rather than copying the board. Circulate and check that students starting item 3 are adding rather than subtracting, since the truck brings water in.

Close and formative check (5 min): Each student writes one sentence on an index card naming the use they would give water to first and one reason. Collect the cards at the door and sort them into two piles, those that give a reason and those that do not, which tells you who needs the sentence frame again tomorrow.

Two Days Without a Tap at Marigold Park School — Grade 2 Social Studies & Civics
Name: ____________________________ Date: ______________

Student Handout

Read aloud: Marigold Park School filled jugs before the water was shut off. Keep track of the gallons. Use cubes, a number line, or numbers.

  1. The school stored 80 gallons. On Monday the kitchen used 25 gallons. How many gallons were left?
  2. The school had 55 gallons left. Hand washing used 20 gallons. How many gallons were left then?
  3. On Tuesday a truck brought 40 more gallons. The school had 35 gallons before the truck came. How many gallons did the school have after the truck came?
  4. The school had 75 gallons. The garden used 18 gallons. How many gallons were left?
  5. The school planned to use 90 gallons in two days. It really used 63 gallons. How many fewer gallons did the school use than it planned?

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: 55 gallons.
    80 - 25 = 55. Counting back by tens from 80 to 60, then back 5 more, reaches 55.
  2. Answer: 35 gallons.
    55 - 20 = 35. Taking away two tens moves 55 down to 35.
  3. Answer: 75 gallons.
    35 + 40 = 75. The truck adds water, so this problem is addition.
  4. Answer: 57 gallons.
    75 - 18 = 57. Students may take away 20 to reach 55, then add back 2.
  5. Answer: 27 gallons.
    90 - 63 = 27. The school used 25 for the kitchen, 20 for washing, and 18 for the garden, which is 63 gallons in all.

Differentiation

Support

Give these students a printed number line from 0 to 100 marked in fives, and let them hop the subtractions instead of writing them. Reduce the handout to items 1, 2, and 3, and read each problem aloud twice before they begin.

Extension

Ask these students to plan a third day. They choose how many gallons the school starts with, name two uses with amounts, and write the two subtraction problems a classmate would have to solve. They should also write one sentence saying which use they would cut first if the truck did not come.

ELL supports

Pre-teach gallon, jug, and shut off with the real jug in hand and a mimed turn of a valve. Post the frame "___ should get water first because ___." Allow students to draw the four school uses and rank them by number before they write anything.

Extensions

Invite the school custodian in for five minutes to say where the shut-off valve for the building actually is and what happens when a pipe breaks during the school day. A real answer from a person students already know turns the scenario into something they will repeat at home.