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Worksheet Grade 3 Math

Delgado Family Water Log: A Grade 3 Add-Subtract Worksheet

A grade 3 worksheet where students add and subtract a fictional family's daily liter totals to see how fixing a leak changed their water use over a week.

Objectives

  1. Students will add and subtract three-digit numbers to analyze a family's daily kitchen-faucet log.
  2. Students will explain how fixing a leak changed a family's water-use pattern over a week.
  3. Students will name a reason a household might choose to use less water even when a treatment plant supplies plenty.

Vocabulary

Key words: water log, treatment plant, regroup

Teacher overview

The Delgado family, a fictional household used for this worksheet, gets its tap water from the Meadowbrook Water Treatment Plant, a fictional facility that cleans water before it reaches their home. Suppose the family kept a log of how many liters flowed from their kitchen faucet each day for one week, and partway through the week, an adult in the family fixed that kitchen faucet, which had been dripping for months. This worksheet uses that week of data to give students real three-digit addition and subtraction practice while showing how one repair changed the family's pattern of faucet use.

Delgado Family Water Log: A Grade 3 Add-Subtract Worksheet — Grade 3 Math
Name: ____________________________ Date: ______________

Student Worksheet

Use the water log below to answer the questions.

Day Liters used at the kitchen faucet
Monday 132
Tuesday 145
Wednesday 138
Thursday 98
Friday 105
Saturday 112
Sunday 95

A leak was fixed on Wednesday night.

  1. Add Monday and Tuesday. What is the total?
  2. Compare Tuesday and Wednesday. Which day is more? By how many liters?
  3. Add Thursday and Friday. These are the first two days after the fix.
  4. Subtract Sunday from Saturday. What is left over?
  5. Add Thursday, Friday, and Saturday. This is the three-day total after the fix.
  6. Add Monday and Tuesday. Then add Friday and Saturday. Which pair is more? By how many liters?
  7. Find the lowest day. Find the highest day. What is the difference?
  8. Add up all seven days. What is the week's total?
  9. Thursday, Friday, and Saturday are lower than Monday and Tuesday. Why? Use the leaky faucet in your answer.
  10. A water plant sends plenty of clean water to homes. Give one reason a family might still use less.

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: 277 L. 132 + 145 = 277.
  2. Answer: Tuesday used more, by 7 L. 145 − 138 = 7.
  3. Answer: 203 L. 98 + 105 = 203.
  4. Answer: 17 L. 112 − 95 = 17.
  5. Answer: 315 L. 98 + 105 + 112 = 315.
  6. Answer: The Monday-Tuesday pair used more, by 60 L. Monday + Tuesday = 132 + 145 = 277. Friday + Saturday = 105 + 112 = 217. 277 − 217 = 60.
  7. Answer: 50 L. Sunday had the lowest total (95 L) and Tuesday had the highest (145 L). 145 − 95 = 50.
  8. Answer: 825 L. 132 + 145 + 138 + 98 + 105 + 112 + 95 = 825.
  9. Answer: Answers will vary, but should explain that fixing the dripping faucet on Wednesday evening stopped water from being wasted continuously, so the days after the fix (Thursday, Friday, Saturday) show lower totals than the days before it (Monday, Tuesday).
  10. Answer: Answers will vary. Accept any reasonable reason, such as saving money on the family's water bill, conserving a shared resource that other households also depend on, or reducing the energy needed to treat and pump the water in the first place.

Differentiation

Support (below grade level)

Provide a place-value chart (hundreds, tens, ones) alongside the water log so students can line up digits before adding or subtracting, and reduce the worksheet to items 1 through 7, skipping the full seven-day total in item 8.

Extension (above grade level)

Have students calculate the family's daily average for the three days before the leak was fixed (Monday, Tuesday, Wednesday) compared with the three days after (Thursday, Friday, Saturday), without using a calculator, and explain in writing which average is lower and by roughly how much.

ELL supports

Pre-teach "log," "leak," and "treatment plant" with simple picture supports: a clipboard with checkmarks for "log," a dripping faucet for "leak," and a labeled building diagram for "treatment plant." Allow items 9 and 10 to be answered with short phrases instead of full sentences.