Classroom activity Grade 1 Science

Two Cups and a Tube at Jessamine Court: A Grade 1 Activity

Pairs pour colored water into a U-shaped tube, raise one end, and build a model showing why the town keeps its water tank up high above the school.

Grade: Grade 1
Subject: Science
Material: Classroom activity
Time: 35 min
Prep: Moderate prep
Materials: Clear plastic tubing about two feet long, one length per pair, taped into a U on a cardboard backing, Two clear cups per pair to steady the ends and catch drips, A small funnel per pair and a pitcher of water tinted with one drop of food coloring, A shallow tub or towel under each work space, A book per pair for Round 2, Paper and crayons for the tank sketch, Student Handout, one per pair

Standards

K-2-ETS1-2 NGSS

Develop a simple sketch, drawing, or physical model to illustrate how the shape of an object helps it function as needed to solve a given problem.

How this material aligns: In step 5 each pair draws the tall tank, the sloping pipe, and the school below, then labels the arrow showing how the tank's height lets water reach the tap without a pump.

All materials for K-2-ETS1-2 →

1.MD.C.4 Common Core Math

Organize, represent, and interpret data with up to three categories; ask and answer questions about the total number of data points, how many in each category, and how many more or less are in one category than in another.

How this material aligns: Handout item 4 sorts the three rounds into the categories moved toward A, moved toward B, and stayed level, so the finished sorting shows how many rounds fall in each one.

All materials for 1.MD.C.4 →

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This material is in the public domain (CC0) and may be copied, edited, and shared freely, without attribution. Updated 2026-09-04.

Objectives

Students will observe that water in a U-shaped tube rests at the same height on both sides.
Students will sort three rounds of the test by which way the water moved.
Students will draw a model showing how a tank's height sends water down to a school tap.

Vocabulary

Key words: tube, level, tank, flow

Teacher overview

The fictional town of Jessamine Court keeps its water tank on the hill above the school, and this activity gives first graders the reason in a form they can hold in two hands. Pairs pour tinted water into a clear tube bent into a U and watch it settle at the same height on both sides, then raise one end and watch the water run toward the low side until the two sides line up again. The model maps onto the concept directly, because the tube is the town's pipe, the two open ends are the tank and the school tap, and the height difference between them is what makes water move. Pairs work at one tub each, and the activity ends when every pair has run all three rounds and drawn the tank sketch.

Activity Directions

Set up (before class). Bend each length of tubing into a U and tape only the bottom bend to a piece of cardboard, leaving both arms free above the tape so they can be lifted, and label one end A and the other end B. Set the cardboard in a shallow tub and prop it upright against a box or the side of the tub so both open ends point up, with a cup beside each end to catch drips. Have the tinted water and a funnel ready at each work space.
Introduce the question (5 min). Ask the class how water gets from the town tank all the way to the sink in the classroom, and whether anything has to push it. Take two or three ideas and leave the question open.
Teach the pour (5 min). Model filling one U tube. Put the funnel in end A and pour slowly until the water shows in both arms, then stop. Point out that the water climbed up the far side on its own. Remind pairs to pour slowly, keep the cardboard upright, and let the tub catch anything that spills.
Run the three rounds (15 min). Round 1: both ends are held at the same height, and pairs mark where the water sits on each side. Round 2: one partner holds a book beside the tube and lifts end A up by the thickness of the book while the other watches which way the water moves. Round 3: one partner lifts end A up as high as the tubing allows while the other watches again. Pairs record each round on the Student Handout before starting the next one. Circulate and ask pairs to say which side was higher before they say which way the water went.
Draw the model (7 min). Each pair draws the Jessamine Court tank standing on its hill, the school down below, and the pipe running between them, then adds an arrow showing which way the water travels and labels the tank as the high end. Ask pairs to point on their own drawing to the part that does the same job as end A in Round 3.
Debrief (3 min). Ask two questions and take several answers each. First, in which round did the water refuse to move, and what was the same about both ends that round? Second, what would happen to the school tap if the town moved the tank down to the parking lot beside it? The activity ends once both questions are answered and every pair has a finished sketch.

Two Cups and a Tube at Jessamine Court: A Grade 1 Activity — Grade 1 Science

Name: ____________________________ Date: ______________

Student Handout

Your tube has two ends. One end is A. One end is B. Pour the water in slowly. Then run three rounds and write what you see.

Round	What you do
Round 1	Both ends are held at the same height
Round 2	End A is lifted up by the thickness of a book
Round 3	End A is held up high

In Round 1 both ends were at the same height. Tell where the water sat in the tube.
In Round 2 end A was lifted up a little. Which way did the water move?
In Round 3 one end was held up high. Which way did the water move?
Sort your three rounds. Write each round under moved toward A, moved toward B, or stayed level.
Draw the tank on the hill, the school below, and the pipe between them. Draw an arrow to show which way the water goes.
Write one sentence. Tell why the town keeps the tank up high instead of down beside the school.

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: At the same height on both sides.
With both ends level, the water settles to one line straight across the two arms of the tube.
Answer: Toward end B.
Raising end A by the thickness of a book makes B the low side, so water runs that way until the two water lines match again.
Answer: Toward end B, and faster than in Round 2.
The bigger the height difference between the two ends, the more strongly the water runs to the low side.
Answer: Round 1 under stayed level, Round 2 under moved toward B, Round 3 under moved toward B.
Accept a mirrored sorting if a pair labeled their ends the other way around, as long as the round with both ends at the same height is the one under stayed level.
Answer: Accept any drawing with the tank above the school.
The drawing needs a pipe joining the two and an arrow pointing from the tank down toward the school, with the tank labeled as the high end.
Answer: Accept any answer naming height as the cause of the flow.
Sample response: the tank sits up high so the water runs downhill through the pipe to the school all by itself.

Differentiation

Support

Pair these students with a partner who handles the pouring while they take the watching job and report which side is higher each round. Give a cut-and-paste handout for item 4 with three round labels and three category boxes, and pre-draw the hill outline for item 5 so only the pipe and the arrow need adding.

Extension

Ask pairs to raise end A slowly and find how high it can go before water starts to spill out of end B, and describe that position in a sentence. Pairs can also predict what happens if both ends are lifted together to the same new height, then test the prediction and say whether it held.

ELL supports

Pre-teach "tube," "level," "tank," and "flow" while running one slow demonstration pour, naming each word at the moment students can see it. Provide the sentence frames "The water moved toward ___" and "The tank is ___ than the school," and accept the item 6 answer as a labeled drawing.

Extensions

Walk the class to a window that looks toward a real water tower, standpipe, or hilltop tank, and ask students to point out which is higher, the tank or the school. Students who have run the tube rounds can then predict what the crew would have to add if a new neighborhood were built on ground higher than the tank itself, which is exactly where a booster pump station goes.