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Classroom activity Grade 5 Math

Hallamby Water Fair Trade-Up: A Grade 5 Capacity Activity

A grade 5 trading game at a fictional town's water fair where teams exchange cup cards for pints, quarts, and gallons, then convert hose lengths as well.

Objectives

  1. Students will convert cups to pints, quarts, and gallons within the customary system.
  2. Students will solve multi-step problems that mix two customary units, such as gallons and quarts.
  3. Students will convert yards to feet and feet to inches.

Vocabulary

Key words: cup, pint, quart, gallon, convert

Teacher overview

This is a trading game for teams of four, set at the fall water fair in Hallamby, a fictional town that runs a water-saving week every year and asks families to measure how much they use. Each team begins with a pile of cup cards and visits three trading posts, where the posted rule turns two cups into a pint, two pints into a quart, and four quarts into a gallon. Because a team may only trade at the rate on the sign, exchanging the cards carries out each conversion step by step, and a team that ends holding the fewest cards has traded up correctly at every post. The misconception this activity targets is multiplying in both directions, so that a student who correctly finds 16 cups in a gallon also answers that 32 cups must be 512 gallons.

Activity Directions

  1. Before class, set up three tables. The Pint Post sign reads "2 cups make 1 pint." The Quart Post sign reads "2 pints make 1 quart." The Gallon Post sign reads "4 quarts make 1 gallon." Put a stack of pint cards at the first post, quart cards at the second, and gallon cards at the third, and place a real cup, pint, quart, and gallon container on a display table where every team can see them.
  2. Set the scene (6 min): Explain that Hallamby hands out water at its fair in cups, and that the fair crew has to report the total in the largest containers it can. Hold up the four real containers in order and pour from one into the next so the class sees each rule before it appears on a sign.
  3. Teach the rules (5 min): Give each team a starting pile of cup cards. A team may trade only at a post, only at the rate on that post's sign, and only in one direction, from smaller containers to larger ones. Leftover cards that cannot be traded stay in the team's pile.
  4. Round one (8 min): Give every team 24 cup cards. Teams move through the posts in order and trade as far up as the rules allow. The round ends when a team can make no more legal trades or when 8 minutes have passed, whichever comes first. Record each team's ending pile on the board.
  5. Round two (8 min): Give every team 40 cup cards and run the same trading. Forty cups trade up to 20 pints, then to 10 quarts, and 10 quarts make 2 gallons with 2 quarts left over, so every team should finish holding 2 gallon cards and 2 quart cards rather than rounding the leftover away.
  6. Handout (8 min): Students complete handout questions 1 through 10 at their seats, working alone and checking answers with a teammate at the end.
  7. Debrief (5 min): Ask one team to explain why the number of containers got smaller every time they traded up while the amount of water stayed the same. Then ask what a team would have to do to trade a gallon card back into cup cards, and write both directions on the board as multiplication and division.
Hallamby Water Fair Trade-Up: A Grade 5 Capacity Activity — Grade 5 Math
Name: ____________________________ Date: ______________

Student Handout

Hallamby hands out water at its fair in cups. The fair crew reports totals in the largest containers it can. Use these rules: 2 cups make 1 pint, 2 pints make 1 quart, and 4 quarts make 1 gallon.

  1. How many cups are in 1 pint?
  2. How many cups are in 1 quart?
  3. How many cups are in 1 gallon?
  4. A team has 24 cups of water. How many pints is that?
  5. A team has 24 cups of water. How many quarts is that?
  6. The crew has 3 gallons of water. How many quarts is that?
  7. The crew has 3 gallons and 2 more quarts. How many quarts is that in all?
  8. A team has 32 cups of water. How many gallons is that?
  9. A hose at the fair is 4 yards long. How many feet long is it?
  10. That same hose is 12 feet long. How many inches long is it?

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: 2 cups.
    The Pint Post sign gives the rule directly: 2 cups make 1 pint.
  2. Answer: 4 cups.
    A quart is 2 pints and each pint is 2 cups, so 2 x 2 = 4 cups.
  3. Answer: 16 cups.
    A gallon is 4 quarts and each quart is 4 cups, so 4 x 4 = 16 cups.
  4. Answer: 12 pints.
    Going from a smaller unit to a larger one calls for division: 24 divided by 2 = 12 pints.
  5. Answer: 6 quarts.
    Each quart is 4 cups, so 24 divided by 4 = 6 quarts. Checking against question 4, the 12 pints trade two for one into 6 quarts.
  6. Answer: 12 quarts.
    Going from a larger unit to a smaller one calls for multiplication: 3 x 4 = 12 quarts.
  7. Answer: 14 quarts.
    The 3 gallons give 3 x 4 = 12 quarts, and adding the 2 loose quarts gives 12 + 2 = 14 quarts.
  8. Answer: 2 gallons.
    Each gallon is 16 cups, so 32 divided by 16 = 2 gallons. An answer far larger than 32 means the student multiplied instead of dividing.
  9. Answer: 12 feet.
    Each yard is 3 feet, so 4 x 3 = 12 feet.
  10. Answer: 144 inches.
    Each foot is 12 inches, so 12 x 12 = 144 inches.

Differentiation

Support

Give these teams a printed conversion ladder with cup at the bottom and gallon at the top and the rule written on each rung, and let them keep it at the table during trading. Start them with 16 cup cards rather than 24 so the first round trades up to exactly one gallon with nothing left over, which makes the pattern visible before leftovers appear.

Extension

Ask these teams to work the trading backward: starting from 3 gallons, how many separate cup cards would the fair crew need to hand out, and how many trades at each post would that take. Have them write the answer as a chain of multiplications and check it against a teammate's chain.

ELL supports

Label the four real containers on the display table with word cards reading "cup," "pint," "quart," and "gallon" in English and, where possible, in students' home languages, and keep the containers nested so the size order is visible. Provide a sentence frame for the debrief: "When I traded up, the number of containers got ___ because each container held ___."

Extensions

Have students time how long the classroom sink takes to fill a quart container, then estimate how many quarts and gallons the class would use washing hands once each. Ask them to write their estimate in gallons and quarts together, the way the Hallamby fair crew reports its totals, and to name one change that would lower the number.