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Science (2015) Grade(s): 2


Provide evidence that some changes in matter caused by heating or cooling can be reversed (e.g., heating or freezing of water) and some changes are irreversible (e.g., baking a cake, boiling an egg).

Unpacked Content

Scientific and Engineering Practices

Engaging in Argument from Evidence

Crosscutting Concepts

Cause and Effect


Students know:
  • Characteristics of materials before heating or cooling.
  • Characteristics of materials after heating and cooling.
  • Characteristics of materials when heating or cooling is reversed.


Students are able to:
  • Analyze evidence to support a claim that heating and cooling causes change in matter.


Students understand that:
  • Heating or cooling a substance may cause changes that can be observed. Sometimes these changes are reversible and sometimes they are not.


  • Properties
  • Evidence
  • Change
  • Matter
  • Heating
  • Cooling
  • Reversible
  • Irreversible