Enrichment · STEM Explorations

Test it three times.
Change one thing.

A prototype gets better one test at a time, as long as every test answers a clear question. Write the requirement as a number, run the same trial three times, and note exactly where it failed. The log works out the mean against the target, warns when one trial is doing the work of three, and lines up every version side by side.

Log a testWhat you get
$5one-time · every device you sign in on
Buy · $5

Included with the Caveat Academy pass and Whole-school licenses. Or get it in the STEM explorations set, $49 for 9 items.

Your tests

The worked example is made up: a cardboard truss bridge that held a mean of 4.5 kg as version 1 and 6 kg as version 2 after one change, against a 5 kg requirement. Tests save on this device only.

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What you get

Enrichment · STEM Explorations$5

What you finish with
A record per test with project, version, date and what changed; the requirement as a target with a direction and unit; method and conditions; every trial’s measurement and notes; how it failed and the next change. Computes the mean and whether it meets the target; flags a single trial, a miss and trials that missed under a passing mean; lists the mean of every version.
Who it is for
Middle and high school students in engineering, robotics, physics and science fair projects, and the teachers who run design challenges.
Format
Browser log with a saved record per test. Prints one test, all versions as a table or a blank test sheet; downloads a spreadsheet (.csv); exports and imports a file.
Access
$5 one-time, yours on every device you sign in on; the tool opens once you are signed in with it. Included with the Caveat Academy pass and Whole-school licenses. Also in the STEM explorations set ($49) and the Enrichment Suite pass ($119), and 1 more bundle. Everything you type stays in this browser; nothing is sent to Caveat.
Where it lives
The STEM Explorations space in Caveat Enrichment.
Support
Questions about access, an order or a correction: team@caveatacademic.com.

How to use it

  1. Turn the goal into a measurable requirement with a target and a unit.
  2. Write the method so that every trial runs the same way.
  3. Run at least three trials and log each one.
  4. Write where and how it failed.
  5. Choose one change for the next version, then log its test as a new record.

Log a test

One turn of the loop

The design loop12345You logsteps 3 to 51. Define the requirement2. Build a version3. Test it, three trials4. Find the failure5. Change one thingThe design loop12345You logsteps 3 to 51. Define the requirement2. Build a version3. Test it, three trials4. Find the failure5. Change one thing
Engineers loop many times. Each record here is one turn of the loop for one version.

Why three trials

Any single trial mixes the design with luck: a weak glue joint, a slightly different load point. Three or more trials under the same conditions show how much results vary. If they spread widely, fix the method before you change the design.

Why one change

Change the braces and the glue and the cardboard at once, and a better result cannot tell you which change mattered. Engineers call each changed factor a variable; changing one per version keeps the record readable. When a deadline forces two changes, write both down.

Sources

  1. NGSS Lead States. Next Generation Science Standards: Engineering Design, MS-ETS1 and HS-ETS1 (nextgenscience.org).
  2. NASA. The Engineering Design Process for educators (nasa.gov/stem).
  3. TeachEngineering, University of Colorado Boulder. Engineering Design Process (teachengineering.org).
  4. National Institute of Standards and Technology. NIST/SEMATECH e-Handbook of Statistical Methods: replication and measurement variation (itl.nist.gov).

The worked example is made up. Follow your teacher’s safety rules for loads, tools and materials. Nothing you type is sent to Caveat. Support: team@caveatacademic.com.