Quiz & test questions Grade 3 Engineering & Design

Coppergate Screen Choice: A Grade 3 Design and Math Quiz

A grade 3 quiz where students work out daily cleaning times for three bar screens at a fictional plant, then choose the screen that meets both goals.

Grade: Grade 3
Subject: Engineering & Design
Material: Quiz & test questions
Time: 30 min
Prep: No prep
Materials: None

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: Item 6 weighs three proposed bar screens against a stated cleaning time limit and a stated wipe catch goal, and item 7 explains the trade the fastest screen forces, which is the solution comparison this standard names.

All materials for 3-5-ETS1-2 →

3.OA.A.1 Common Core Math

Interpret products of whole numbers, e.g., interpret 5 x 7 as the total number of objects in 5 groups of 7 objects each. For example, describe a context in which a total number of objects can be expressed as 5 x 7.

How this material aligns: Items 1 through 3 read each screen's cleanings per day as equal groups of minutes and multiply to find the daily total, the interpretation of products this standard describes.

All materials for 3.OA.A.1 →

3.OA.D.8 Common Core Math

Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.

How this material aligns: Item 4 takes two steps, multiplying to find one screen's daily cleaning minutes and then subtracting the crew's time limit, the two-step word problem this standard requires.

All materials for 3.OA.D.8 →

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This material is in the public domain (CC0) and may be copied, edited, and shared freely, without attribution. Updated 2026-09-23.

Objectives

Students will multiply to find the daily cleaning minutes for each screen.
Students will compare three screens against a time limit and a catch goal.
Students will explain why the quickest screen is not the best choice.

Vocabulary

Key words: screen, bar, goal, limit

Teacher overview

This 30-minute quiz is worth 20 points and holds a short design review for a fictional treatment plant, with five computation items, two short-answer items, and one multiple-choice item. Students find the daily cleaning time for three bar screens, read the results of a wipe test, and then pick the screen that meets both of the plant's stated goals. Students often assume that anything sent down a drain breaks apart on the way, and packages that say flushable make that idea stronger, so they are surprised that a wipe arrives at the plant still whole and can jam a screen or a pump. Naming that before the quiz helps students see why a screen with narrow gaps is worth extra cleaning time.

Coppergate Screen Choice: A Grade 3 Design and Math Quiz — Grade 3 Engineering & Design

Name: ____________________________ Date: ______________

Assessment

The town of Coppergate cleans the water that leaves its homes and shops. The dirty water flows into the plant along a channel. A bar screen sits across the channel and catches rags, sticks, and wipes. Workers rake the trash off the screen by hand.

The plant tested three screens. Workers dropped 10 wipes into the water above each screen and counted how many wipes slipped through. The crew has only 20 minutes a day for screen cleaning.

Screen	Gap between bars	Cleanings each day	Minutes for one cleaning	Wipes that slipped through
Screen A	5 centimeters	2	6	8 of 10
Screen B	2 centimeters	4	6	1 of 10
Screen C	2 centimeters, with a rake bar	4	4	1 of 10

(2 points) Screen A is cleaned 2 times a day. Each cleaning takes 6 minutes. How many minutes a day does Screen A take?
(2 points) Screen B is cleaned 4 times a day. Each cleaning takes 6 minutes. How many minutes a day does Screen B take?
(2 points) Screen C is cleaned 4 times a day. Each cleaning takes 4 minutes. How many minutes a day does Screen C take?
(3 points) The crew has only 20 minutes a day for screen cleaning. How many minutes over that limit is Screen B?
(3 points) Screen A let 8 wipes slip through. Screen B let 1 wipe slip through. How many more wipes slipped past Screen A than Screen B?
(3 points) The plant set two goals. A screen may take no more than 20 minutes of cleaning a day. A screen may let no more than 2 wipes slip through in a test of 10. Which one screen meets both goals?
(3 points) Screen A takes the least cleaning time each day. Explain why the plant should still not choose Screen A.
(2 points) Why did the crew drop the same number of wipes above every screen?
- A) To make the test fair
- B) To fill the channel with water
- C) Because the screens were new
- D) To wash the bars clean

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: 12 minutes. Two cleanings of 6 minutes each is 2 × 6 = 12 minutes a day.
Answer: 24 minutes. Four cleanings of 6 minutes each is 4 × 6 = 24 minutes a day.
Answer: 16 minutes. Four cleanings of 4 minutes each is 4 × 4 = 16 minutes a day.
Answer: 4 minutes. Screen B takes 4 × 6 = 24 minutes a day, and 24 − 20 = 4 minutes over the crew's limit.
Answer: 7 wipes. Screen A let 8 wipes through and Screen B let 1 through, so 8 − 1 = 7 more wipes slipped past Screen A.
Answer: Screen C. Screen C takes 16 minutes a day, which is under the 20-minute limit, and it let only 1 wipe through, which is under the limit of 2. Screen A fails the wipe goal with 8, and Screen B fails the time goal with 24 minutes.
Answer: Screen A misses the wipe goal by a wide margin. Accept any answer noting that its 5-centimeter gaps let 8 of 10 wipes pass, so the wipes travel on to jam pumps further inside the plant, and saving cleaning minutes does not make up for that.
Answer: A) To make the test fair. Dropping 10 wipes above every screen keeps the test the same for each one, so the different results come from the screens rather than from the number of wipes.

Differentiation

Support

Give these students a blank three-row chart with the words cleanings, minutes, and total already printed, so items 1 through 3 become a fill-and-multiply task. Allow counters or repeated addition in place of multiplication, and let students circle the winning screen on the table before writing item 6.

Extension

Ask these students to design a fourth screen that beats Screen C on both goals and to say what part of the screen they changed. Have them name one new problem their change might cause, such as a rake bar that needs its own repair time.

ELL supports

Pre-teach screen, gap, rake, and slip through with a simple drawing of bars across a channel. Provide the sentence frame "Screen ___ takes ___ minutes a day, so it ___ meet the goal." Allow item 7 to be answered with a labeled drawing showing wipes passing between wide bars.

Extensions

Have students weigh a fifth option in which the plant keeps Screen A but adds a second screen behind it. Ask them to list the goals that option meets, the extra cleaning time it adds, and whether the plant should build it.