Journey to the Earth’s Core





Name of Activity Journey to the Earth’s Core
Author Kristen Burns and Sarah Halpert
Keywords sturdy car, rock, travel, ramp, layers, earth, crust, mantle, core, axles, bushings, car, density, plate tectonics, mass, friction
Subject Simple Machines
Grade Level 4, 5, 6
Time 1 Hour Total
Brief Description The kid’s needed to design a sturdy car that will hold a rock (small pebble). The car will then
travel down a ramp that is labeled with the layers of the earth. The upper half of the ramp
was the crust and the lower half of the ramp was the mantle. The floor directly after the ramp
was labeled the outer core and following the outer core was the inner core section. The kids
had to adjust the axles and bushings on the car to allow it to travel farther. Once the cars were
finished we tested them on the ramp to see how far into the “earth” they went.
Lesson Objectives: Review density and how to measure the mass of an object

Build a sturdy car and tweak it to allow it to travel the furthest down the ramp

Learn the layers of the earth

Materials Needed: Simple Machine Kit

Materials for a ramp

Paper to cover the ramp that depicts the layers of the earth

Small rocks


Preparation and Set Up: Get a large piece of paper and cut it down to fit the ramp while allowing some extra to account
for the outer and inner core section. Design the paper with fun facts about each layer
(temperature, thickness, etc.).
Necessary Background Vocabulary:

Plate Tectonics


Axle and Bushing


Procedure 1. Explain density and the theory of plate tectonics. Also, review how to measure the mass of an object. 2. Have them start building the cars. Make sure that the cars have a spot to hold the rock and that they are sturdy. Explain how to adjust the bushings to account for less friction. 3. Take the mass of the rock. 4. Test the cars on the ramp and see how far into the “earth” they were able to travel. 5. Fill out the worksheet.
Extensions: If a group finishes early ask them if they can make the car go further.

Retrieving the Core





Name of Activity Retrieving the Core
Author STOMP
Keywords core, earth, magnetic, sample, NXT, invention, earth’s core, magnet
Subject NXT
Grade Level K, 1, 2, 3, 4, 5, 6
Time 2 Hours Total
Brief Description Students will use their NXT vehicles they built in lesson 1 to retrieve a sample of the magnetic core of the Earth.
Lesson Objectives: - To learn about the layers of the Earth.
- To build a retrieving device.
- To travel to the “Core”, retrieve a sample and travel back.
Materials Needed: - Engineering Design Sheet
- Pre-constructed NXT vehicles (from lesson 1)
- Computers running MINDSTORMS software
- Additional motors
- LEGO building pieces
- Pre-built model of the Earth’s core with magnets dispersed around
- The Magic School Bus: inside the Earth by Joanna Cole
- Lego Reflection Response Sheet
Preparation and Set Up: - Create and set up a model Earth (ideas and photos attached).
- Collect materials
- Make copies of activity worksheets
- Engineering Design Sheet
- Engineer’s Programming Sheet
- Programmer’s Icon Sheet
- Arrange students in groups of two
- Give each group their NXT vehicle, an extra motor, extra LEGO pieces (you can also give them a magnet and tape for their retrieval device)
Necessary Background Attached is a sheet with references that have information about the layers of the Earth.
Earth’s core
  1. Start by reviewing the inside of the Earth and it’s layers. Questions you might ask are:
    1. What are the layers inside of the Earth called? (crust, mantle, outer core, inner core)
    2. What is the crust made of? Who can name the 3 types of rock found their? (igneous, metamorphic, sedimentary)
    3. Who can tell me about the mantle? The core?
  2. Read The Magic School Bus: Inside the Earth to the students to facilitate discussion on the layers of the Earth and connect to previous activities.
  3. Discuss the core of the Earth, explaining the difference between the outer core and inner core. Review what the children know about magnets.
  4. Divide the class into groups of 2 students. Explain that they will use the “School Bus” they made in lesson 1 (the NXT vehicle) for this challenge.
  5. Tell the students that the design challenge is to build and program your “School Bus” to collect a magnetic sample from the core of the Earth.
  6. Write the challenge on the board:
    1. Using the model of the core, explain that the NXT car must travel to the core.
    2. Once in the inner core, the collecting invention must collect a sample from the core.
  7. Explain to students that they will be allowed to use another motor for this challenge.
  8. Brainstorm some ideas of what might work to retrieve the rock sample. Write ideas on the board for future reference.
  9. Distribute the “Engineering Design Sheet” (attached) to each student.
  10. Model how to fill out these worksheets. Let the students complete their designs before they can begin to build.
  11. Allow students to build their inventions.

Note: If this lesson is going to be taught in 2 class periods, this is a good time to stop.

  1. If possible, bring up MINDSTORMS on a computer and mirror it on a TV monitor so that all the students can see. If not, model it to a few students at a time around a computer.
  2. Have each student fill out an “Engineer’s Programming Sheet” (attached) to complete before they program their NXT. Students can cut an paste icons from the “Programmer’s Icon Sheet” on to the programming sheet.
  3. When students have finished planning, let them program on MINDSTORMS and download their program to their NXTs.
  4. Allow students to test their designs on the model Earth (examples of model Earths are attached).
  5. Bring the class together. Let each group demonstrate their design. When all the groups have had a chance to show their design, review today’s activity:
    1. What were some difficulties that students encountered while building? How did they overcome these difficulties?
    2. What were some difficulties that students encountered while programming? How did students fix their programs?
    3. Did any students have to redesign?
    4. Review the layers of the Earth.
Extensions or Modifications: After retrieving the sample of the core, turn the Magic School Bus around and go back
through the mantle and the crust to the surface of the Earth.
Reference 1
Reference 2
Reference 3
Reference 4
Reference 5
Reference 6

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