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Learning Resource Type

Classroom Resource

Heating Can Make a Change That Cannot Go Back Again

Subject Area





In this lesson, students will be able to explain that when some substances are heated to a certain extent, they change in a way that cannot be changed back by cooling them.  

Students see a time-lapse video of cookie dough being baked into cookies. Students participate in a class discussion about heat-causing changes that cannot be reversed when cooled. Students learn that heating baking powder in the cookie dough makes gas and causes little holes in the cookie. Students design and conduct an experiment to see if baking powder causes more bubbling when it is warm or cold.

    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



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


    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.

    Scientific and Engineering Practices

    Engaging in Argument from Evidence

    Crosscutting Concepts

    Cause and Effect
    Link to Resource

    CR Resource Type

    Lesson/Unit Plan

    Resource Provider

    American Chemical Society

    License Type