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Science Rocks!

Guess My Rule


your results

Sent in by:
Katie of Storrs, CT

Common characteristics rule in this guessing game.

Materials Needed

  • 10-20 different objects (like shoes, pencils, pens, rocks, coins, paper clips, small toys, etc.)
  • a friend



  1. First, group together a few objects that have something in common, like size or color. (You don't need to use all the objects.)
  2. Then have your friend guess the "rule" you used to group the objects. (For example, they are short. Or, they are red.)
  3. To help your friend figure out the rule, he or she can think of an object that is not in the group and ask if it belongs. You can only answer "yes" or "no".
  4. Switch roles. Let your friend make a group of objects, and then you try to guess the rule.
  5. When you notice how objects are similar or different, you're thinking like a scientist. Scientists put things into groups by looking at how they are alike or different. This is called classification. For example, one way scientists classify trees is by their leaves: Trees that drop their leaves each year are called deciduous; trees that don't drop their leaves are called evergreen. When scientists find a new type of tree to classify, they ask "yes" or "no" questions to decide which group it belongs in. If they ask, "Does this tree drop its leaves each year?" and the answer is "yes", then the tree is deciduous.

Now it's time for you to experiment. Try making up different rules for the same collection of objects. Or use the same rule for a different collection of objects. What happens if you use only two objects? Can someone still guess your rule? Send your best rule to ZOOM and tell us what objects fit into the group.

Some of your Results

Kylie, age 9 of OK wrote:
My friends couldn't guessmy rule it was really fun.

Brianna, age 10 of Woodlake, CA wrote:
When they all tried to guess my rule they all got it wrong so they all gave up!

Cortney, age 12 of Slinger, WI wrote:
But at the end we had great fun playing over and over again!!!

Veronica, age 9 of Houston, TX wrote:
I had two gatoraids and an apple juce pack{all full} and my rule was full. it took alot of guesses for someone to guess it. Some people thought it was sport drinks and someone else thought it was all made by the gatorade company. I think that was my hardest rule.

Neha, age 8 of New York, NY wrote:
I did the experiment with my brother. The easy ones he got right. The hard ones I told him.

Jasemar, age 11 of Brooklyn, NY wrote:
It was a great nath game that me and my family enjoyed, also Ive seen this game almost everyday in my school math book.

Lauren, age 10 of Colorado Springs wrote:
I did the game at my Birthday party and none could get it and I had to tell them.

Kalene, age 11 of Cheboygan, MI wrote:
I couldnt fool my friends on my shape rule and they couldnt fool me on there rules - types and size.

Murphy, age 13 of Naperville, IL wrote:
I used a bunch of objects and sorted them into two categories. One of the categories was Objects whose words contained double letters. And objects whose words did not contain double letters. It was really hard for my friends to figure out the grouping. After 15 minutes of my friends struggling, they finally figured it out.

Antoinette, age 10 of Jacksonville wrote:
I took scissors and cut out different kinds of triangles. I drew a circle and put the triangies in it. Example: Put in 2 right triangles and 1 icossilies triangle. My rule would be right triangles. Names of triangles: Right tri, straight tri, Icossilies tri, equalateral tri.

Chloe, age 9 of Boise, ID wrote:
My rule was smell and we used candles and things that had a strong fragrence and it took my friends a while to figure it out.

Allie, age 8 of Toccoa, GA wrote:
I got things that were circular and nobody got it for a long time!

Nathaniel, age 8 of Toccoa, GA wrote:
I got things that were very fragile and it was a turtle shell that had no turtle it and a starfish. It took a long time to figure out it.

Todd, age 8 of Honolulu, HI wrote:
Rule was "purple and long" and was 12 guesses long.

Brittany, age 10 of Lansing, MI wrote:
My class and I did one and hade to guess that they were wearing shorts and I guessed right, I'm reaporting on guess my rule.

Veena, age 11 of Traverse City, MI wrote:
Me and the class played guess my rule last year and one of the rule was wearing earings ad I got it right. It is fun to play and I think other people should play it.

Cinthya, age 9 of Brooklyn, NY wrote:
When I tride this, I thout that it was a game because it saunded like a game & it looked like a game. It was fun!

Janice, age 15 of Hemmynsville, MB wrote:
That group thing with a rule was fun! I did that at home with my 5th grade brother. I used a challenging rule! How they feel. Rough, smoth, and soft.

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