🇺🇸 NGSS · Grades 6-8

MS-ETS1-3: Comparing design test results

MS-ETS1-3 explained: analyzing test data from several designs to combine their best features into a better solution, with a worked example and quiz.

NGSS performance expectation MS-ETS1-3

Students who demonstrate understanding can: Analyze data from tests to determine similarities and differences among several design solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success.

Grade band
Grades 6-8
Discipline
Engineering design
Topic
Engineering Design

Official wording from the Next Generation Science Standards (NGSS Lead States, 2013). NGSS is a registered trademark of WestEd. Neither WestEd nor the lead states and partners that developed the NGSS were involved in the production of this page, and they do not endorse it. View on nextgenscience.org

What MS-ETS1-3 means

Three teams build three different paper towers, and each one is best at something different: one is tallest, one survives a fan, one uses the least paper. Rather than simply picking a winner, students analyze test data to see which characteristics made each design succeed or fail, and then combine the strongest features into a new design that better meets the criteria.

Good analysis starts with fair tests, where the same conditions and measurements are used for every design. Students organize results in tables or graphs, compare them against the criteria, and look for causes: did the wide base explain stability, or the triangle bracing? Repeated trials help separate real differences from chance. The goal is not to prove one design is perfect, but to learn which features deliver which benefits.

This is how real products improve from one version to the next: engineers test, compare, and blend the most effective ideas.

Students should be able to

  • Organize test results from several designs in a table or graph.
  • Compare each design's results against the criteria for success.
  • Identify which features of each design caused its strengths and weaknesses.
  • Propose a new design that combines the best features of the tested designs.
  • Explain why repeated trials and fair tests make comparisons more trustworthy.

Common misconceptions

The design with the best single result is best overall

A design might win on one criterion but fail another. Every criterion must be considered together.

One trial is enough

Results vary from trial to trial. Averaging several trials gives a more reliable picture of how a design performs.

Losing designs have nothing to offer

A design that fails overall can still contain a feature that works well and is worth combining into the next version.

Tests can change between designs

If the test conditions differ, such as a stronger fan for one tower, the comparison is not fair.

Worked example: combining the best features

Three model cars are tested on the same ramp, 3 trials each. Car A (large wheels): 210, 190, 200 cm. Car B (light frame): 160, 170, 150 cm. Car C (narrow body): 180, 175, 185 cm. Which features should be combined?

  1. Find each car's mean distance: A = (210 + 190 + 200) ÷ 3 = 200 cm; B = (160 + 170 + 150) ÷ 3 = 160 cm; C = (180 + 175 + 185) ÷ 3 = 180 cm.
  2. Car A traveled farthest, suggesting large wheels reduce the effect of bumps and friction.
  3. Car C was second and its trials were close together, suggesting the narrow body runs consistently.
  4. A new design could use Car A's large wheels with Car C's narrow body, then be retested under the same conditions.

Answer: Car A averaged 200 cm, Car C 180 cm and Car B 160 cm; combining A's large wheels with C's narrow body is a promising new design to test.

Teaching MS-ETS1-3

Run a short design challenge where teams must share results on a class data table. Ask each team to name one feature from another team's design they would borrow and why. Graphing means with the range of trials makes both performance and consistency visible.

Assessment items often give a table of test results for several designs and ask which features to combine, with justification from the data.

6 practice questions

Original questions written for this standard. Choose an option or type your answer, then press Check. Every question has a worked explanation.

Score: 0 / 6(0 of 6 checked)
  1. 1.

    Why should every design be tested under the same conditions?

    Question 1 options
    Answer and explanation

    Answer: C) To make the test fair so results can be compared

    Keeping conditions the same means differences in results come from the designs, not the test.

  2. 2.

    A design's three trials held 4, 6 and 5 kg. What is the mean load?

    Answer and explanation

    Answer: 5 (also accepted: 5 kg)

    (4 + 6 + 5) ÷ 3 = 15 ÷ 3 = 5 kg.

  3. 3.

    Design X is the strongest but too heavy; Design Y is light but weak. What is the best next step?

    Question 3 options
    Answer and explanation

    Answer: A) Look for features that give strength without much weight and combine them

    Analyzing what makes each design succeed lets you combine strengths into a better solution.

  4. 4.

    Why run several trials for each design?

    Question 4 options
    Answer and explanation

    Answer: D) Results vary, so averages are more reliable

    Repeated trials reduce the effect of random variation.

  5. 5.

    What is the word for making a new version of a design based on test results?

    Answer and explanation

    Answer: iteration (also accepted: iterate, redesign, optimization, improving)

    Engineers iterate, using test data to make improved versions.

  6. 6.

    A tower survives the fan test only when it has a wide base. What does this suggest?

    Question 6 options
    Answer and explanation

    Answer: B) A wide base improves stability

    The data link the wide base to surviving the wind, so it is a feature worth keeping.

Builds on

Leads to

  • MS-ETS1-4: Models for iterative design testing →
  • HS-ETS1-3

    Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.

Teach MS-ETS1-3

Make a lesson on MS-ETS1-3

A full lesson with slides, activities and an exit ticket on comparing design test results, pitched to grades 6-8 and editable in PowerPoint or Google Slides.

Make a lesson →

Make a worksheet

A printable, differentiated worksheet on MS-ETS1-3 with an answer key, ready in about a minute.

Make a worksheet →

Build a self-marking test

Turn comparing design test results into a quiz students answer online that marks itself, with a class summary for you.

Build a test →

FAQ

What is the main goal of MS-ETS1-3?

To analyze data from tests of several designs and identify the best characteristics of each so they can be combined into a better solution.

What kinds of data work for MS-ETS1-3?

Any measured results against the criteria, such as distances, loads held, times or temperatures, organized in tables or graphs.

More engineering design standards

MS-ETS1-1: Defining criteria and constraintsMS-ETS1-4: Models for iterative design testing
All Middle school science standards →Standards home →