Classroom activity Grade 3 Science

Oakenshaw Farm's Three Ways to Water a Row of Beans

A 50-minute grade 3 station rotation comparing flooding, sprinkling, and drip watering on soil trays, with one liter of water measured for each fair trial.

Grade: Grade 3
Subject: Science
Material: Classroom activity
Time: 50 min
Prep: Moderate prep
Materials: Three shallow trays with small drain holes, Potting soil to fill the trays, plus extra dry soil to refill them between groups, Nine sponge strips cut to stand upright as plants, A one-liter pitcher marked in milliliters, A cup with pinholes in the bottom, Three drinking straws and a cup for the drip line, Three clear catch cups, Six blocks or thick books to raise the trays, Paper towels, Masking tape and a marker

Standards

3-5-ETS1-2 NGSS

Generate and compare multiple possible solutions to a problem based on how well each is likely to meet the criteria and constraints of the problem.

How this material aligns: Teams compare three watering designs against the same two criteria, wet soil at the plants and little water lost out the bottom, then argue which design fits the farm best; the extension asks them to generate a fourth design of their own.

All materials for 3-5-ETS1-2 →

3.MD.A.2 Common Core Math

Measure and estimate liquid volumes and masses of objects using standard units of grams (g), kilograms (kg), and liters (l). Add, subtract, multiply, or divide to solve one-step word problems involving masses or volumes that are given in the same units, e.g., by using drawings (such as a beaker with a measurement scale) to represent the problem.

How this material aligns: Students measure exactly one liter of water for each of the three stations so the comparison is fair, which is the liquid-volume measuring half of this standard; the activity does not include its word-problem half.

All materials for 3.MD.A.2 →

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This material is in the public domain (CC0) and may be copied, edited, and shared freely, without attribution. Updated 2026-07-23.

Objectives

Students will measure one liter of water for each watering method so the test stays fair.
Students will compare three watering designs against the same two criteria.
Students will choose one design for the farm and support the choice with what they observed.

Vocabulary

Key words: irrigate, flood, sprinkle, drip line, criteria, runoff

Teacher overview

This is a three-station rotation for groups of four, built around trays of soil that stand in for one bean row on the fictional Oakenshaw Farm. Each station waters the row a different way, and every station gets exactly one liter of water so the only thing that changes is the method. Students see for themselves how much water runs straight through the tray and out the drain hole instead of reaching the sponge strips that stand for plants. A common idea worth addressing is that more water always means healthier plants, so the recording sheet keeps attention on how much water was lost rather than on how much was poured.

Activity Directions

Set up the trays (10 min). Fill three shallow trays with soil to the same depth and poke three small drain holes in the bottom of each. Stand three sponge strips upright in a line down the middle of every tray to stand for bean plants. Set each tray on two blocks over a clear catch cup so anything that drains out is collected. Label the trays Flood, Sprinkle, and Drip with masking tape.
Introduce the farm problem (5 min). Tell students that the fictional Oakenshaw Farm has one row of beans and a limited amount of water in a dry summer. Write the two criteria on the board: the soil right at the plants must be wet, and as little water as possible should run out the bottom.
Show the three designs (5 min). At the Flood station, one liter is poured over the whole tray at once. At the Sprinkle station, one liter is poured through the pinhole cup and moved back and forth over the whole tray. At the Drip station, one liter is poured slowly into a cup feeding three straws that end at the base of the three sponge strips.
Measure the water (3 min). Show students how to fill the pitcher to the one-liter mark at eye level. Every station uses one liter, no more and no less. Say plainly that changing the amount would spoil the comparison.
Rotate and run the stations (18 min). Groups spend six minutes at each station. At each one they water the tray by that station's method, wait one minute, then look at the catch cup and at the soil around the sponge strips. Every student records the station on the handout before rotating. Before the next group arrives, empty the catch cup, squeeze out the sponge strips, and replace the tray's soil with dry soil to the same depth. Wipe up spills right away, and have students wash their hands after touching the soil.
Ending condition (1 min). The rotation ends when every group has run all three stations and filled in all three rows of the recording table.
Rank the designs (4 min). Each group puts the three designs in order from best to worst against the two criteria written on the board, and marks the ranking on the handout.
Answer the handout questions (2 min). Students finish the numbered questions on their own so their reasoning is on paper before the discussion begins.
Debrief (2 min). Ask which design left the most water in the catch cup, and ask what a farmer with a limited amount of water would give up by choosing the flood method. Point out that the design that used water best is not the one that looked wettest overall.

Oakenshaw Farm's Three Ways to Water a Row of Beans — Grade 3 Science

Name: ____________________________ Date: ______________

Student Handout

Oakenshaw Farm is a fictional farm with one row of beans. Every station gets exactly 1 liter of water.

Station	How wet is the soil at the sponge strips?	How much water is in the catch cup?
Flood
Sprinkle
Drip

Which station left the most water in the catch cup?
Which station left the least water in the catch cup?
Which station left the soil wettest right at the sponge strips?
Every station got 1 liter of water. Why did each station have to get the same amount?
Name one thing that stayed the same at all three stations besides the amount of water.
Which design would you choose for Oakenshaw Farm in a dry summer? Name the station.
Give one reason for the choice you made in question 6. Use something you saw at the stations.
Water in the catch cup did not reach the bean plants. Where would that water go on a real farm?

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: Answers will vary by setup. In most classroom runs the Flood station leaves the most water in the catch cup, because a liter poured all at once runs through the soil faster than the soil can hold it. Accept any station the group actually recorded, as long as the answer matches their table.
Answer: Answers will vary by setup. The Drip station usually leaves the least in the catch cup, since the water enters slowly at three points. Accept any station supported by the group's own recorded observation.
Answer: Answers will vary by setup. The Drip station usually leaves the soil wettest at the sponge strips, and the Sprinkle station is often close behind. Accept the station the group recorded.
Answer: To keep the test fair. Accept any answer explaining that the comparison only tells you about the method when the amount of water is held the same, and that a station with more water would look better for the wrong reason.
Answer: Accept any real control from the setup, including the same soil depth, the same tray size, the same number of sponge strips, the same waiting time before looking, or the same number of drain holes.
Answer: Accept any of the three stations, as long as question 7 gives a reason drawn from the group's observations. The Drip station is the most common choice.
Answer: Answers will vary. Accept any reason tied to the two criteria, such as the drip line putting water where the plants are or the flood method sending too much water out the bottom. Do not accept a reason based only on which station was the most fun to run.
Answer: It would soak deeper into the ground or run off the field. Accept answers naming water sinking below the roots, running downhill into a ditch or creek, or carrying soil away with it.

Differentiation

Support

Give these students a recording sheet with picture choices, such as three raindrop sizes to circle for how wet the soil is and three cup drawings to circle for how full the catch cup is. Assign them the pouring job at each station so they handle the one-liter measurement, and pair them with a partner who writes.

Extension

Ask students to design a fourth station for the fictional Oakenshaw row that they predict will beat the drip line on both criteria. They should list the materials, name the one thing they changed, explain how they would keep every other condition the same, and then run it if time and materials allow.

ELL supports

Pre-teach "flood," "sprinkle," "drip," and "soak" by demonstrating each one with water on a paper towel before the rotation begins. Post a picture card at every station showing the pouring method. Provide the frames "The ___ station left ___ water in the cup" and "I would choose ___ because ___."