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Science Rocks!

Penny Cup Game


your results

Sent in by:
Kim of Deltona, FL

Two heads are better than one, but what about two eyes?

Materials Needed

  • short glass cup
  • at least 8 pennies
  • pen and paper for charting
  • a few friends
  • table and chairs



  1. To test whether two eyes ARE better than one, try to see how many pennies you get into a cup with both eyes open and with one eye open.
  2. Sit at a table across from your partner. Have her hold a penny in her hand and move it around in the air above the cup.
  3. When you say "drop it!" your partner should drop the penny. Did it get in the cup? Try it 8 times and write down how many times the penny landed in the cup.
  4. How do you think you'll do if you close one eye? Predict whether you'll get more or fewer pennies in the cup.
  5. Now try it! Repeat the test with 8 more pennies, this time with one eye closed. Write down how many times you got the penny in the cup.
  6. After the first player is done, switch and try again.
  7. When everyone has had a chance with both eyes and one eye, compare your results. Do you see a pattern? Which way seemed easier?

You probably found a difference between using just one eye and two. That's because the brain uses information from both eyes to tell how far away something is. Also, the information your brain gets from each eye is a little bit different. To see this hold up your two pointer fingers in front of you with one in front of the other. Look at them with both eyes then, close your right eye. Then, open your right eye and close your left eye. You should see a slightly different view.
Could you do something to help your brain figure out how far away the penny is when you have only one eye open? Would it help if you taped a second penny to the side of the cup? Or would it make a difference if you closed your left eye instead of your right eye? Whatever you find out, be sure to send your results to ZOOM!

Some of your Results

Joane, age 11 of Olympia, WA wrote:
well me and my friends tried it and we all got the pennies in with both of our eyes open, but when we had to close our eyes, it got harder! and everyone kept missing!

Ashiantek, age 12 of Arcadia, FL wrote:
actually it was easier to get more pennies in the cup using only one eye

Brian, age 8 of Blaine, MN wrote:
It was better with both eyes open. Results were the same with one eye only even though I thought I would do better with my left eye.

Lindsey, age 11 of Baldwinsville wrote:
One person from each team had a blindfold on. There was a cup on a chair and you would thow the penny and how has the most pennies in the cup. It worked.

Morgan, age 12 of McAlisterville, PA wrote:
My brother and I did it together. We both got all the pennies in teh cup with our eyes open, but we didn't do very good with one eye closed. He got 5 in, and I got 2 in. It is really hard!

Aden, age 6 of Woodbine, MD wrote:
6 rigrt and 2 wrong.

Courtney, age 11 of Middletown, NJ wrote:
I tried it and I saw a pattern. The pattern was that it was easier to do it with one eye open and the other one closed. It was easier for me, but for my friends it was the opposite.

Eliza, age 13 of San Gabral, CA wrote:
What I know is that I'm nearsighted, and then it was easy! Maybe nearsighted people see better then normal sighted people!

Luke, age 7 of St. John's wrote:
I got all the pennies on my fourth try.

Anna, age 10 of Los Angeles, CA wrote:
When I had tow eyes opened I got them all right. Then when I had only one eye opened I missed a couple.

Ruth, age 9 of Yellow Springs, OH wrote:
My friend Maeve and I got completly diffrent scores in the one eye but we got the same scores with two eyes. In two eyes we both got 8, but with one eye I got three but Maeve got seven! Can you belive it thats like allmost a perfecet score.

Priyanka & Niweatha of Toronto, ON wrote:
Me and my friend both got 10 out of 10 for 2 eyes. For my righ eye I got 4 out of 10 she got 6 out of ten. For left eye I got 3 out of 10 for her left eye she got 2 out of ten.

Caroline, age 10 of Mississauga wrote:
I took two popsicle sticks and I taped them on to two sides of the cup and it helped me get more pennies in with one eye closed. Try it it works have fun.

Liz, age 10 of Tamarac, FL wrote:
I got 8 out of 8 with both eyes and 5 out of 8 with 1 eye. When my mom tryed it she only got 7 the first and and 2 with 1 eye. Then we played with dimes and we both got 5 every time.

Nathan, age 11 of San Jose, CA wrote:
My results were:with eyes open: 8 right 1 eye closed: 4 right My sister Wyes open: 8 right 1 eye closed: 2 right

Mckenzie, age 9 of Everett, WA wrote:
My friend Joe and I did this game and insted of using a cup we used a basket and here are our results Joe got 8/8 on both one eye and two eyes I got 7/8 on one eye and 8/8 on two eyes. Those are our results.

Maggie, age 8 of Belleview, FL wrote:
First I did it with both eyes and I got 7 hits and 1 miss. Then I did it with my right eye and I got 4 hits and 4 misses. Then I did it with my left eye and I got 3 hits and 5 misses. I knew I would miss more with my left eye because I am getting glasses for astigmatism on Monday.

Travis, age 7 of Moseley, VA wrote:
When I had one eye closed, I was able to get 5 out of 8 in the cup. Then with both eyes open, I was able to get all of them in the cup.

Toby, age 10 of San Lorenzo wrote:
I got all of the pennies in with both eyes open. But with only 1 eye, I just got 3 pennies in. This was so cool.

Emily of Galena, IL wrote:
I tired on my grandma she can't do it with both eyes but I can do it I made up to 8.

Jessica, age 13 of Chicago, IL wrote:
I got 3 out of seven my first time!!!

Stephanie, age 9 of Wellington, FL wrote:
When I did it I got all of them in even with one eye!

Mee, age 13 of Pontiac, MI wrote:
When I use both eyes I got more pennies into the cup.

Michael, age 10 of Tigard, OR wrote:
When I tried it with two eyes I got 8 out of 8. When I tried it with one eye I got 8 out of 8. Both left eye and right eye.

Rebekah, age 10 of Pawnee, IL wrote:
I found out that domanat eyes (the one you can't close) are better than your non domant eyes.

Tara, age 8 of Churubusco, NY wrote:
When I Closed my left eye I got 7 out of 10 and thats pretty good. When I closed my right eye I got 5 out of 10.

Fiona, age 11 of Richmond, ME wrote:
When my Dad did it he got 8 out of 8 for 1 eye open and both eyes open. For me, I got 5 out of 8 for one eye open and for both eyes open I got 8 out of 8.

Elline, age 10 of Streamwood, IL wrote:
When I tryed it I got 8 pennys withmy eyes open and I had 6 pennys with one of my eyes open.

Katherine, age 7 of Chicago, IL wrote:
I got 8 when eyes open and the same result with 1 eye open.

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