CurriculumGrade 3Science

Fair Tests to Improve a Design

Aligned to 3-5-ETS1-3 — Next Generation Science Standards.

What this lesson teaches

A fair test changes only one thing at a time so you know what made the difference. Fair tests help you find which part of a design to fix.

Worked example

To make a paper airplane fly farther, you throw it the same way each time and only change the wing folds.

Practice questions

  1. Build a simple model, like a paper boat, and decide one thing you will change.
  2. Test it while keeping everything else the same, and measure the result each time.
  3. Explain which change worked best and what you would improve next.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

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En español

Pruebas justas para mejorar un diseño

Una prueba justa cambia solo una cosa a la vez para que sepas qué hizo la diferencia. Las pruebas justas te ayudan a encontrar qué parte de un diseño arreglar.

Ejemplo: Para que un avión de papel vuele más lejos, lo lanzas de la misma manera cada vez y solo cambias los dobleces de las alas.

More Engineering Design lessons

Comparing Solutions3-5-ETS1-2

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