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Science Rocks!

Balls and Ramp


your results

Sent in by:
Barbara of Brookline, NH

Gravity - not just a good idea. It's the Law! Use the Law of Gravity to tell time.

Materials Needed

  • marbles
  • paper towel rolls
  • construction paper
  • tape
  • a flight of stairs
  • gravity - do not try this aboard the MIR Space Station



  1. Try to make a clock that measures exactly 10 seconds.
  2. The only materials you can use are marbles, paper towel rolls, construction paper, tape, and a flight of stairs.
  3. If the marble gets to the bottom of the stairs in exactly 10 seconds, without any help from you, you've mastered our challenge!

Some of your Results

Andrew, age 11 of Toledo, OH wrote:
The ball fell straight down of the ramp onto the ground and bounced a few times then rolled.

Gabby, age 10 of MT wrote:
it was fun but there was no point to it. I still liked it but I had tried it before but it didnt work out that well. but I got to say that it was fun I guess.

Paige, age 9 of Fort Myers, FL wrote:
the ball rolled off the ramp at the top part

Harrison, age 9 of Greenville, SC wrote:
I used my plastic marble set and I had so much downward ramps it was a laughing matter! I also put in a jump and when the marble hit the jump it went 2 feet and hit a target in 10 sec.

Matthew, age 7 of CT wrote:
It went down a big rap, looped around and went flying into a tupe ramp down and up in air again and landed safely on the ramp and on land!

Trey, age 9 of Rocky Mount, NC wrote:
The ball rolled super fast!

Austin, age 10 of Sumner, WA wrote:
The ball fell off at the bottom, it got great speed.

Roxana, age 10 of NY wrote:
First I puted a light ball and it went slow then I put aheavey ball and it went fast. It was fun.

Andrew, age 8 of Calgary, AB wrote:
My first try it was 29 seconds and then I pushed it down the ramp and looked inside and it got stuck for a while. So I put a diffrent paper towel roll on it. I tried it but it was 9 seconds!!! So I thought it needs just a little more so I put about 2 cm. I put the marble down the ramp and it worked.

Alex, age 8 of Demarest, NJ wrote:
When I did the balls and ramp the ball kept breaking through the last turn.

Thomas, age 5 of Decatur, IL wrote:
We set up cardboard on a table and made u and triangle shapes for the ball to run in. We used a metal ball from our magnet set.

Lucas, age 5 of Raleigh, NC wrote:
My suggestion: Try putting shutters on the bottom of the ramp and a puley on top. Then the ball can drop off when you want it to.

Oscar, age 12 of El Paso, TX wrote:
I rolled a tennis ball into the ramp and it went preety far but when I rolled the golf ball into the ramp it ramped even more. You just need someone to roll the balls and a ramp. A ruler too, to measure.

Jackson, age 8 of Garden Grove, AZ wrote:
When I test it was perfect. But the ball was stuck in the bridge.

Ariba, age 10 of Bethelem, PA wrote:
When I did the balls and ramp I builded a high ramp and the balls rolled down very fast.

Tamika, age 13 of New York City, NY wrote:
All the balls had the same time and they all went pretty fast.

Brianna & Olivia of Deltona, FL wrote:
I used ten sheets of paper and string and tape. It went from one ramp to the other. I standed up on the table while Olivia holds one end of the string and I hold the other. WE taped the ten sheets of paper together and taped the end of each paper to the end of each ramp.

Jr, age 11 of South Gate, CA wrote:
I made a realy long tunnel, and when I rolled the marble down, it took about 10 seconds for the marble to reach the end of tunnel. The tunnel took a LLOOONNGGG time to make but I got to use it for other things too. I made it out of T. P. rolls and tape...

Haley, age 8 of New Castle, PA wrote:
It went down the ramp into the cup that tipted and spilt the water.

Kimberly, age 14 of Mahatton, NY wrote:
It was easy to put the balls on the ramp I made and zoom!

Andrea, age 12 of Farmington Hills wrote:
It was hard to get it to be exactly 10 seconds, it was either 11 or 9. The first time it wouldn't start so I gave it a push and it got down at exactly 10 seconds. That was the only time I could get it to be exactly 10 seconds!

Brianna M., age 5 of Fairfax, VA wrote:
I used my blocks to make a ramp at the bottom of the ramp.

H. T. of Boston, MA wrote:
It like lasted for a minute. I did a very long zig-zag design. It was radical man!!!

Nolan A., age 7 of Boise, ID wrote:
I used only one step and six rolls and measured the distance, it was 11 inches where the ball landed.

Nicholas B., age 10 of Livermore, ME wrote:
I built a structure with materials. I made more rampways than you. It took 2 tries and I hit 10 seconds.

Zachery wrote:
The marble went really fast!

Max, age 8 wrote:
I did it down the stairs; straight down and it went like way too fast! So I made my ramp go zigzag-eey and it worked so awesome!

Brittany wrote:
When I rolled the ball it stayed in the 1 foot ramp so I gave it a push and it rushed down invisibly. Pretty cool, eh? Just like in pokemon and DBZ

Lisa A., age 11 of Dallas County, TX wrote:
I have an idea to make an alarm clock that goes off in 10 seconds. You need-paper towels, a soccer ball, a flight of stairs, a bike horn, tape, scissors, string, a chair, and a large scale. Do the same thing with the soccer ball, towels, and stairs as you do in the Balls and Ramp experiment. Then tape the scale at the bottom of the stairs, then tape a chair to the ground 4 ft. away from the scale. After that tape the bike horn, squeezy part facing the scale, on the chair. Now tie 1 end of a string to the top part of the scale and the other end to the squeezy part of the bike horn. Make sure the string is tight. Now when the ball rolls downs the ramp (9 and 1/2 seconds) it will push down on the scale, pulling the string that squeezes the bike horn. (1/2 a second, which equals a 10 second alarm clock).

Michelle F. of Woodridge, IL wrote:
It kept going off the ramp!

Drew M., age 10 of Belleville, ON wrote:
When we did it we only got it to go 2 seconds!! We only used rolled up construction paper.

Anthony, age 11 of New Bedford, MA wrote:
When I tried it the balls needed some force. So I decided to use my hand 3ft away. With all my force. And then it worked!

Jamie A., age 10 of Harrison, NY wrote:
My marble got to the bottom of the stairs in 11 seconds on the first try, 9 seconds the second time and 10 seconds the third try. After the first try I took away a few strips of tape off the course. It was just one second away from 10 seconds. I added 2 more strips and I finally got the marble to get to the bottom of the stairs in 10 seconds. This ZOOMsci was a lot of fun.

Charles S., age 11 of Orlando, FL wrote:
I got it to slow down and my record was 16 seconds

Eddie C., age 10 of Millwaukee, WI wrote:
IT WAS WAY TOO FAST!!!!!!!! We didn't use toilet paper rolls.

Ben N., age 9 of New Orleans, LA wrote:
When I did it the ramp broke and the balls rolled away.

Lori S., age 13 of Chicago, IL wrote:
When I did the balls and ramp, I got it to go for 27 seconds. Can you top that???

not yet implemented