CurriculumGrade 4Science

Energy-Changing Machines

Aligned to 4-PS3-4 — Next Generation Science Standards.

What this lesson teaches

Devices can change energy from one form into another to do a job. A flashlight changes stored energy in a battery into light, and a wind-up toy changes motion you make into motion that moves the toy.

Worked example

A hand-crank flashlight changes the motion of your turning hand into electric energy, and that electric energy becomes light — with no batteries needed.

Practice questions

  1. Look at a wind-up or battery-powered toy. What energy goes into it, and what energy comes out?
  2. Sketch a simple device that turns moving water into spinning motion, like a water wheel.
  3. Design a toy that changes one kind of energy into another, and describe how it works.

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

Máquinas que cambian la energía

Los aparatos pueden cambiar la energía de una forma a otra para realizar un trabajo. Una linterna cambia la energía guardada en una pila en luz, y un juguete de cuerda cambia el movimiento que tú haces en movimiento que mueve al juguete.

Ejemplo: Una linterna de manivela cambia el movimiento de tu mano al girar en energía eléctrica, y esa energía eléctrica se convierte en luz — sin necesidad de pilas.

More Physical Science lessons

Energy and Energy Transfer4-PS3Waves: Amplitude & Wavelength4-PS4How Energy Travels4-PS3-2When Things Collide4-PS3-3How We See Things4-PS4-2Sending Messages with Patterns4-PS4-3

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