CurriculumGrade 2Science

Can It Change Back?

Aligned to 2-PS1-4 — Next Generation Science Standards.

What this lesson teaches

Heating or cooling can change things — some changes can go back the way they were, and some cannot.

Worked example

Water freezes into ice and can melt back into water, but a cooked egg can never turn back into a raw egg.

Practice questions

  1. Watch an ice cube melt and tell if it could freeze again.
  2. Sort these into 'can change back' or 'cannot': melting butter, burning toast, freezing juice.
  3. Explain why toasting bread cannot be undone.

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

¿Puede Volver a Ser Igual?

Calentar o enfriar puede cambiar las cosas — algunos cambios pueden regresar a como estaban antes y otros no.

Ejemplo: El agua se congela en hielo y puede derretirse de nuevo en agua, pero un huevo cocido nunca puede volver a ser un huevo crudo.

More Physical Science lessons

Properties of Matter2-PS1Best Material for the Job2-PS1-2Take Apart, Build Again2-PS1-3

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