A 60-minute lesson in which students will explore the way solids, liquids, and gases change in different situations.
Prior to conducting the lesson, review the procedure and equipment required for the experiment. As the liquids will require an adequate amount of time to freeze (the length of a school day or overnight), the activity will need to be carried out over two lessons.
½ cup of water
3 x clear containers/beakers/glasses
½ cup measuring cup
½ cup of milk
½ cup of sunflower oil
This lesson contains a link to an external video. Please watch the video prior to presenting this lesson to ensure that the content is appropriate for your students.
Encourage the class to recall all the information they can about solids, liquids, and gases. Record their responses on the board as a mind map.
Ask the students if it is possible for a substance to change its state of matter e.g. for a solid to turn into a liquid. Invite them to share their ideas about if/how this is possible and to give examples.
Watch the Change of State video on YouTube. Encourage the students to take notes. Afterwards, invite the students to share any information from the video that they feel is important.
Explain to the students that they will be working in small groups to investigate how changing the temperature of a substance may affect its state of matter. Provide them with a copy of the Science Experiment – States of Matter. Read through the experiment step-by-step and answer any questions the students may have about the task.
Discuss the ‘Test Design’ and ‘Hypothesis’ sections of the experiment worksheet, then have the students independently complete these sections. Afterwards, assist the students in collecting and preparing the equipment required for the experiment.
Support the students as they complete Step 2 and Step 3 of the method. The remaining steps will need to be completed once the liquids have been in the freezer for an adequate amount of time e.g. the length of a school day or overnight.
Once the liquids have frozen, distribute the beakers to the students. Allow them to record their observations regarding the effects of lowering the temperature of the liquids. Once completed, ask the students to complete the discussion questions and write a conclusion for the experiment independently.
Gather the class back together and encourage the students to share their results from the experiment. Review the discussion questions and share conclusions. Ask the students:
What did you discover?
What can you learn from your results?
How might this information be useful for scientists?
Collect the students’ experiment booklets. These could be included in a portfolio of work samples and used to assess the students’ understanding of the unit objectives.
Encourage the students to think about the slime created in Lesson 1. Discuss how it might change if placed in a freezer or heated to a higher temperature.
Revisit the States of Matter Word Wall. Add the words ‘change’, ‘temperature’, ‘heating’, ‘melting’, ‘vaporization’, ‘sublimation’, ‘cooling’, ‘condensation’, ‘freezing’, and ‘deposition’ to the display.
Students requiring extension could design an experiment that investigates the effects of heating substances.
Allow students that require assistance to work on the experiment at their own pace, providing additional time where necessary.
Suggested Assessment Strategies
used strategic whole class or individual questioning
observed student participation during learning activities