Overview
Procedure

Anchoring Phenomenon

Materials are made of matter. We can observe misshapen objects, including a crayon, lip balm, and a candle.

Lesson Concept

Planning and conducting an investigation to determine evidence that can be used to construct a claim that some changes causes by heating or cooling can be reversed and some cannot.

Investigative Phenomenon

Crayons are made of wax in a shape that we can hold with our fingers. Birthday candles are made of wax in a shape that we can put on a cake. Lip balm is made of wax in a shape that we can apply to our lips.

Standards

Click here for NGSS, CCSS-ELA, and California ELD standards.

Time | Materials | Advance Preparation

Time

90–120 minutes

Part I30–60 minutesEngage
Part II60 minutes
30 minutesExplore
15 minutesExplain/Evaluate
15 minutesElaborate

Part I

Engage (30–60 minutes)

Observations combined with prior knowledge are used to infer the causes of changes to properties of matter.

  1. Bring the students to a central area and have them guide you in drawing a picture on chart paper of what the students recall doing to explore reversible and irreversible changes in the last lesson. Be sure to label and clarify students’ current thinking and wonderings. Any student questions should be added to the 2.1.C1: Student Question Chart.
  2. Review with students the 2.1.C1: Student Question Chart and ask them, “Which of these questions have we answered?” Add student responses to the chart. ESRs: responses will vary depending on the students’ questions.
  3. Ask students: “Which questions are you still curious about?” Support student curiosity and autonomy by providing opportunities and materials for students to explore their as yet unanswered questions. Encourage students to elaborate on what evidence will be necessary to answer their questions.

Part II

Explore (30 minutes)

Collaboratively plan and carry out an investigation to gather evidence to support or refute ideas about causes of changes to matter due to heating and cooling.

    TEACHER NOTE

    This Explore helps students make the connection to the anchoring phenomenon via their learning in Lessons 2.1: Properties of Matter through 2.4: Reversible and Irreversible Changes.

  1. Ask students to recall their ideas from Lessons 2.1: Properties of Matter through 2.4: Reversible and Irreversible Changes and think-pair-share about whether the changes to the misshapen objects are reversible or irreversible. Display the anchoring phenomenon: Materials are made of matter. We can observe misshapen objects, including a crayon, lip balm, and a candle. Chart student ideas. ESRs: I think the misshapen candles and crayons are reversible changes because they’re like the chocolate bar. I disagree; I think the candles and crayons are irreversible because we’ll never get them back to their real shape so they can do their job. I disagree because sometimes it changes shape, but when it is a solid, it can still do its job.
  2. Brainstorm with the students: “What does it mean to undergo a reversible change?” ESRs: We can get it back to its regular shape. We can get it back so it can do its job. The object has to be a solid. The properties are the same as the regular one. A property like shape helps it do its job. Chart student responses.
  3. Brainstorm with the students: “What does it mean to undergo an irreversible change?” ESRs: We cannot get it back to its regular shape. We cannot get it back so it can do its job. The object can be a liquid or a solid so the properties may not be the same. Chart student responses.
  4. Explain to students that they will be developing a plan to conduct an investigation. However, before we begin, we need to agree: “Will we be planning for a reversible or irreversible change? Why?” ESRs: A reversible change because we want the objects to get back to a shape so they can do their jobs.
  5. Guide students to write a plan that results in a reversible change, i.e., getting the misshapen objects to return to their original and useful state or a plan that stops the change from happening altogether. Advise students that they can later write a plan that results in an irreversible change.
  6. Help students craft a question they can use to develop a plan to collaboratively conduct an investigation. ESRs: How can we keep the change from happening? How can we get the misshapen crayon back to a shape so it can do its job? How can we get the misshapen birthday candle back to a shape so it can do its job? How can we get the misshapen lip balm stick back to a shape so it can do its job?
  7. Refer students to the path of learning you have created on chart paper from Lessons 1: Properties of Matter through 4: Reversible and Irreversible Changes. Have students discuss all the different things we did to matter to change it. Now, allow time for them to think-pair-share about any of those ideas they may want to include in their plan.
  8. To create a blueprint to guide students’ thinking, use your chart from Lesson 1: Properties of Matter (refer to 2.1.C2: Engineering Design Process for a sample design process: Imagine, Plan, Create, Test, Improve, Re-create) You can choose to allow students to go through the entire cycle or not. Ask students to identify what materials they will need to carry out their plans.
  9. TEACHER NOTE

    Have students choose one misshapen object they want to focus on to plan an investigation. Be aware of safety concerns in the planning, e.g., you can’t put a metal lip balm stick case in a microwave. Here is a sample student plan that only includes the Imagine and Plan phase:

    Imagine: I can change the shape of the misshapen crayon.

    Plan: First, I would stick the crayon in a microwave to make it a liquid. Then, I would put it in a mold in the shape of a real crayon. Next, I would put it in the freezer to cool. Last, I would use the crayon to color my picture.

  10. Have students compare their plans with a partner and improve their plans.

Explain/Evaluate (15 minutes)

Gather evidence to support or refute ideas about the causes of changes to matter.

  1. Have students refer to their science notebook entries regarding reversible and irreversible changes. Have students use the evidence in their notebook entries from previous lessons to discuss whether their design plan will work.
  2. TEACHER NOTE

    Provide the following sentence frame if your students would benefit:

    I think my plan for ___ will work because ___.

    For example, I think my plan for the crayon will work because it is just like what we did with the chocolate. The chocolate melted and turned to a liquid. Then when we put it in a mold, it became hard again after it cooled. I think the crayon will do the same thing. It will have the same shape and hardness (properties) as the regular one.

  3. Revisit the anchoring phenomenon of misshapen objects. Have students collaboratively discuss: How can you turn an ordinary object into a different shape?
  4. TEACHER NOTE

    Throughout the Matter Unit, a 5E the word model was employed; however, at the end of Lesson 5: The Great Wax Disaster, the final Explain is used to Evaluate student understanding of the anchoring phenomenon. Use this rubric to evaluate students’ plans.

    3
    2
    1
    The plan includes a logical sequence of steps that involve heating/melting and then cooling the misshapen crayon, candle, or lip balm. The plan includes the idea that a solid such as wax, once liquefied, can be put into an appropriate mold, cooled, and then will function as intended.
    The plan includes a somewhat logical sequence of steps that involve some part of heating/melting and cooling the misshapen crayon, candle, or lip balm. May refer to the object being returned to its intended shape for its intended purpose.
    Plan is illogical. Vague reference to heating/melting and cooling the misshapen crayon, candle, or lip balm. Limited to no mention of the object being returned to its original shape for intended purpose.

Elaborate (15 minutes)

Defining and delimiting an engineering problem means generating more than one possible solution to a problem.

  1. Have students complete the 2.1.H1: Engineering Planning Sheet with their plans for how to prevent the objects from becoming misshapen again.