Worksheet Grade 3 Math

Cottonwood Water Works Basins: A Grade 3 Liter Worksheet

A grade 3 worksheet where students add, subtract, multiply, and divide liters of water in the settling basins of a small, fictional treatment plant.

Grade: Grade 3
Subject: Math
Material: Worksheet
Time: 25 min
Prep: No prep
Materials: None

Standards

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 add, subtract, multiply, and divide liters of water across the settling basins in items 1 through 8, the one-step liquid-volume word problems this standard targets.

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 solve one-step word problems about liters of water using all four operations.
Students will explain whether a comparison of two water volumes in liters is true.

Vocabulary

Key words: liter, basin, treatment plant, clean water

Teacher overview

Cottonwood Water Works is a small, fictional plant that cleans water in open tanks called settling basins, where dirt sinks to the bottom and clearer water is left near the top. Every basin in this worksheet is measured in liters, the standard unit third graders use for liquid volume. Students solve eight one-step problems using addition, subtraction, multiplication, and division, then finish with two reasoning items that ask them to judge a claim about the basins. A common error at this grade is choosing the wrong operation, so the teacher note in each answer key entry names the operation the problem calls for.

Cottonwood Water Works Basins: A Grade 3 Liter Worksheet — Grade 3 Math

Name: ____________________________ Date: ______________

Student Worksheet

Cottonwood Water Works cleans water in tanks called basins. All water here is measured in liters.

A basin holds 60 liters of water. A worker adds 20 more liters. How many liters are in the basin now?
A basin has 90 liters. The plant drains 30 liters of dirty water. How many liters are left?
There are 4 basins. Each basin holds 50 liters. How many liters is that in all?
A worker splits 80 liters into 4 equal jugs. How many liters go in each jug?
A tank has 45 liters. A worker adds 45 more liters. How many liters now?
One basin holds 70 liters. A second basin holds 40 liters. How many more liters does the first basin hold?
There are 5 buckets. Each bucket holds 8 liters of clean water. How many liters in all?
A worker sends 100 liters into 5 equal pipes. How many liters go through each pipe?
A worker says that 3 basins of 50 liters hold more than 1 basin of 200 liters. Is the worker right? Tell how you know.
A jug holds 10 liters. There are 6 jugs. Explain how you know the jugs hold 60 liters in all.

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: 80 liters. This is addition: 60 + 20 = 80 liters in the basin.
Answer: 60 liters. This is subtraction: 90 − 30 = 60 liters left.
Answer: 200 liters. This is multiplication: 4 basins × 50 liters = 200 liters.
Answer: 20 liters. This is division: 80 ÷ 4 = 20 liters in each jug.
Answer: 90 liters. This is addition: 45 + 45 = 90 liters.
Answer: 30 liters. This is a compare-subtract: 70 − 40 = 30 more liters.
Answer: 40 liters. This is multiplication: 5 buckets × 8 liters = 40 liters.
Answer: 20 liters. This is division: 100 ÷ 5 = 20 liters through each pipe.
Answer: No. Three basins of 50 liters hold 3 × 50 = 150 liters, and 150 is less than 200, so the single basin holds more.
Answer: 60 liters. Six jugs is 6 equal groups of 10 liters, and 6 × 10 = 60 liters, so the jugs hold 60 liters in all.

Differentiation

Support

Give students base-ten blocks or a labeled beaker drawing so they can model each basin before choosing an operation. Provide a small word bank that pairs signal words with operations ("in all" and "adds" for addition, "left" and "drains" for subtraction, "each" with a total for division). Let students solve items 1 through 4 with a partner before working items 5 through 8 alone.

Extension

Ask students to write two new basin problems of their own, one that uses multiplication and one that uses division, then trade with a partner and solve. Have them predict, before dividing item 8, whether each pipe will carry more or fewer than 50 liters and explain the prediction.

ELL supports

Pre-teach "basin," "drain," "jug," and "pipe" with a simple labeled diagram of a treatment plant. Provide sentence frames for items 9 and 10, such as "The worker is ___ because ___ is ___ than ___." Allow students to show their reasoning with a labeled drawing instead of full sentences where the objective allows.