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How Dense?

Time Frame:
1 class period that runs 60 minutes.

Group Size:
Small Groups


Students will be given a selection of substances and asked to put them in order from least dense to most, similar to layering in Earth. They must justify their choices and be able to write the rationale down. They may make measurements using the equipment of their choice.

Main Curriculum Tie:
SEEd - Grade 7 (2017)
Strand 7.2: Changes to Earth over time 7.2.4

Develop and use a scale model of the matter in Earth’s interior to demonstrate how differences in density and chemical composition (silicon, oxygen, iron, and magnesium) cause the formation of the crust, mantle, and core.


  • Suggestions for substances:
    • clay
    • water
    • vegetable oil
    • rock
    • brick
    • metal bar
    • aluminum can
    • glass marbles or slides
    • ceramic tile
    • gravel
    • cotton
    • styrofoam
  • student worksheet


Student Prior Knowledge:
Students should have had experience finding the density of substances in a variety of ways.

Instructional Procedures:

  1. “Hook” the students with a demonstration of density such as a lava lamp or “dancing spagetti” (broken spagetti noodles in Sprite). Ask students to explain why the bubbles in the lamp move or why the spagetti rises and falls (air bubbles attach to it, lowering the density).
  2. Explain to students that they will be building a model of Earth and it’s layers with the materials you have provided. They must choose a material for each layer of Earth and justify why they placed it in that location.
  3. Show students the materials you have provided and give them the student sheet. Students should be placed in working groups of 3-4.
  4. Go over the introduction and allow students to work and fill in the data. Each group needs to decide on a common plan.
  5. Have each student group present their ideas to the class.

Assessment Plan:
Scoring Guide:

1. Students participate and test materials………………………………….4
2. Students design a logical plan to test materials………………………..4
3. Students accurately test materials………………………………………..4
4. Students report their findings honestly and relate them to Earth……..4

Lesson Design by Jordan School District Teachers and Staff.

Utah LessonPlans

Created Date :
Oct 01 2014 12:37 PM

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