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Classroom activity Grade 1 Engineering & Design

Yarrow Bend's Foot Pedal Tap: A Grade 1 Lever Design Shop

A grade 1 design shop where teams build a cardboard foot lever that lifts a paper tap handle and springs back, so the water stops while hands are soapy.

Objectives

  1. Students will state why a tap left running during hand washing wastes water.
  2. Students will build a lever that lifts a model tap handle when the other end is pushed down.
  3. Students will sketch their lever and label the pivot and the two ends.

Vocabulary

Water conservation
Using less water and using it wisely so there is enough for people and nature now and in the future. Small actions matter, since a faucet dripping once per second wastes roughly 3,000 gallons per year.
Low-flow fixture
A showerhead, faucet, or toilet built to do its job with less water. Swapping in low-flow fixtures is one of the easiest ways for a family to save water.

Teacher overview

Taps in many gyms, kitchens, and hospitals are worked with a foot rather than a hand, and the reason is partly cleanliness and partly water: a pedal tap shuts itself off the moment the foot lifts, so nothing runs while hands are being soaped. This design shop, run in teams of three, has first graders build that mechanism out of a cardboard strip and a block. The model maps onto the real device part for part: the block is the pivot, the far end of the strip is the pedal on the floor, the near end lifts a cardstock tap handle, and a rubber band pulls everything back down when the foot comes off. No water is needed for the build, so the room stays dry and students can focus on the motion. The setting is the make-believe Yarrow Bend School, where the sinks by the cafeteria run the whole time a class washes up before lunch.

Prep is about ten minutes: cut the cardboard strips, cut the tap handles, and set one tray of materials on each table.

Activity Directions

  1. Before class, cut two cardboard strips and one cardstock tap handle per team, and set a tray at each table holding the strips, a block, tape, rubber bands, a paper cup, and the handle.
  2. Gather the class at the classroom sink. Turn the tap on, wash your hands slowly and completely while it runs, and ask students to watch the drain rather than your hands. Ask what went down the drain that nobody used.
  3. Write the problem on chart paper in the class's own words, such as: "The water keeps running while we soap our hands, and nobody uses it." Post it where teams can see it while they work.
  4. Show the mechanism once at the front. Lay a cardboard strip across a block, push one end down with a finger, and let the class watch the other end rise. Name the three parts aloud as you point: pedal end, pivot, handle end.
  5. Put students in teams of three and assign roles: one builder, one holder, one tester. Give one rule before the trays open: the strip has to rest on the block, not be taped flat to the table.
  6. Build, about twelve minutes. Teams tape the paper cup down as the faucet, stand the cardstock handle beside it, and set their strip across the block so that pressing the pedal end lifts the handle. Circulate and ask every team the same question, which is the check for understanding: "Which part of your lever is doing the lifting?" A team that points to the pivot or the handle end is ready; a team that shrugs should be sent back to step 4 with your finger on the block.
  7. Add the return, about six minutes. Teams stretch a rubber band from the handle end to the table so the lever springs back when the foot lifts. Test it three times in a row and count the springs aloud as a team.
  8. Sketch, about six minutes. Each student draws the team's lever and labels three parts: the pedal end, the pivot, and the handle end. Ask students to add one arrow showing which way each end moves.
  9. End the shop when every team has tested three springs and every student has a labeled sketch. Gather on the rug and work through the Student Handout questions, then close by reading the posted problem sentence and asking whether a foot pedal would fix it.
Yarrow Bend's Foot Pedal Tap: A Grade 1 Lever Design Shop — Grade 1 Engineering & Design
Name: ____________________________ Date: ______________

Student Handout

Read aloud with the class, one question at a time, after the sketches are done.

  1. Which end of your lever did the foot push? Write pedal end or handle end.
  2. What did your lever rest on? Name the part.
  3. When you pushed one end down, what did the other end do? Tell what you saw.
  4. What made your lever come back up after the foot lifted off?
  5. Draw one change you would make so the tap handle lifts higher. Tell why that change would help.

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: Pedal end.
    The foot pushes the end that sits on the floor, which is the far end from the model tap.
  2. Answer: The block, which is the pivot.
    Accept block, pivot, or the taped tube. The point is that the strip rests on something rather than lying flat.
  3. Answer: It went up.
    Pressing one end of a lever down lifts the other end, which is what raises the tap handle. Accept any wording describing the opposite end rising.
  4. Answer: The rubber band.
    It pulled the handle end back down, which brought the pedal end back up. Accept any answer naming the rubber band or its stretch. Teams that skipped the band may say they had to lift it by hand, which is an honest and useful answer.
  5. Answer: Answers vary.
    Accept any drawing with a stated change and a reason, such as moving the block closer to the pedal end so a small push makes a bigger lift at the handle end, or using a taller block.

Differentiation

Support (below grade level)

Tape the block to the table before class so the pivot stays put while these students work the two ends. Give them a picture card of a completed lever with the three parts already labeled, and let them match their build to the card part by part before sketching.

Extension (above grade level)

Ask these students to move the pivot to a new spot on the strip, test again, and describe what changed about how far the handle end travels. They can also design a pedal for a sink used by both a first grader and an adult, and explain what has to be adjustable.

ELL supports

Pre-teach four words with the parts in hand: push, lift, pivot, back. Attach a gesture to each, such as a flat hand pressing down for push and the same hand rising for lift. Handout questions 1 and 2 are two-choice or one-word by design, and questions 3 through 5 may be answered by pointing at the sketch and speaking while an adult scribes.

Extensions

Look for a foot-operated or motion-operated tap somewhere in the building, in the kitchen, the nurse's room, or a staff sink, and take the class to see it work. Ask the person who uses it daily why that tap is set up that way, and compare their answer with the reasons the class wrote on the chart paper.