Teacher Site Map
6th Grade Core
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Journal Entry - Take out your science journal and answer the following question(s) (use drawings as appropriate):

What keeps our solar system in shape?


  • String - 1 meter long
  • Four large metal washers
  • Stopwatch, timer with seconds, or clock with second hand
  • Student worksheet (copy from below or printout as a .pdf document.)


  1. Tie two washers on the end of the string.
  2. Swing it overhead, securely holding one end.
  3. Count the number of revolutions it makes in ten seconds.
    • Use the person’s nose as a reference point.
      Record on your worksheet.
  4. Repeat Step 3.
    Average the two trials.
  5. Fold string in half and repeat Steps 3 and 4.
  6. Add two more washers on the string.
  7. Repeat Steps 3-5.
  8. Complete the remainder of the worksheet.

Student Worksheet

Name ____________________________________________

Problem: Which combination of washers and string do
you think will go the fastest?

Hypothesis: ____________________________________________


Data Table


First Test

Second Test


50 cm., 2 washers


100 cm., 2 washers


50 cm., 4 washers


100 cm., 4 washers


Your experiment:


Analysis Questions:

  • What did the size of the orbit do to the number of
    revolutions the washers made?


  • Which of the planets take longer than the others to
    revolve around the sun?


  • What effect does mass have on a planet’s revolution?


  • What would happen if there was no gravity?


  • What would happen if planets’ forward velocity were
    changed (e.g. slower, faster)?


  • What did your experiment show?


Conclusion: Remember to restate your hypothesis, and the
correctness of your hypothesis, and explain what you
learned. Use the back of your worksheet.



solar_system_image size_motion_distance_image microorganism_image Heat_light_and_sound_image

Get the plug-ins: Get Adobe Acrobat Reader , and Get Quicktime Player. (The QuickTime plug-in is needed to play sounds and movies correctly.)

Want to share photos of you or your friends doing this activity? Send it in an e-mail with the following information:

  1. The title of the activity
  2. The URL (Internet address)
  3. Your name.

Remember that no pictures can be used that show student faces or student names on it. 

Teachers should view the Teacher Site Map to relate Sci-ber text and the USOE 6th grade science core.

Updated October 24, 2008 by: Glen Westbroek

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