The Mysterious Balloons

By Winnie Koo


Students will investigate unknown solids using the sense of touch.

Materials Needed:

3 to 5 small zipper-typed plastic bags or baby food jars, 3 to 5 un-inflated balloons (each with a different color), 1 wide-stemmed funnel, 3 to 5 types of solids: rice, beans, salt, and so forth.


  1. Instruct students to use their senses (except taste) to investigate the set of balloons and answer Questions 1 4 on the "Mystery Solid" Observation Sheet (provided).
  2. After ample investigation time, have the groups record what they believe is inside each of the balloons on the Observation Sheet (as shown below).
  3. Call on each group, asking the spokesperson to tell what the group thinks each of the contents is and to provide some supporting evidence or comments for these conclusions.
  4. Ask students what they might use to help make the task of identifying the balloon contents easier, but remind them that they still shouldn't open or cut the balloons. After discussion, give each group a set of reference containers, telling them that the reference containers hold the same materials as the Mysterious Balloons do.
  5. Ask students to match balloons with the sample containers and to record their matches on their Observation Sheets.
  6. Reveal the actual contents of the balloons and allow students to examine the contents.


Mystery Solids-Observation Sheet

  Balloon-A Balloon-B Balloon-C Balloon-D Balloon-E
1.How does the surface of the balloon look?          
2.Squeeze the balloon. Do you hear any sounds?          
3.Describe how the balloon feels.          
4.Sniff the balloon. Can you smell anything?          
5.What do you think the contents of the balloon are? List reasons for your answers.          
6.Name the actual contents of the balloon.          

Performance Assessment:

Partner pairs of students. Direct each student to explain to their partner how they made their decision about which solid was in the balloon.


Teaching Science with Toys, 1993 

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