skip graphical navigation
PBS KidsZOOM Home Back to Activity
Science Rocks!

Can Car


your results

Sent in by:
Sarah of St. Louis, MO

Vrrroom! Make a racing car out of an old coffee can.

Materials Needed

  • coffee can and two coffee can lids
  • can opener
  • rubber bands
  • masking tape
  • bead
  • pencil
  • paper clip
  • tape
  • unsharpened pencil
  • liquid soap



  1. Cut off the bottom of an empty coffee can with a can opener. Have an adult help you to do this because the edge can be sharp.
  2. Use scissors to punch a hole in the center of both coffee can lids. Make sure the hole is large enough for a rubber band to pass through easily.
  3. Push one end of a rubber band through one of the holes, and hook it around a paper clip on the outside of the lid. Tape the paper clip in place over the hole so that the rubber band cannot pull through the hole. Place the lid with the rubber band on the can.
  4. Reach into the can and grab the rubber band, but be careful of the edges of the can.
  5. Slide the free end of the rubber band through the hole in the other lid, from the inside. Slip the end of the rubber band through a bead so that the bead is on the outside of the lid.
  6. Slide a pencil through the part of the rubber band that is on the far side of the bead from the can, so that the pencil stops the rubber band from pulling back through the bead and the lid.
  7. Adjust the position of the pencil so that the end of it extends past the edge of the can. If it is too short, get a longer pencil.
  8. Put the liquid soap around the edges of the can so that it cuts down the rubbing and slides better.
  9. Wind up the pencil until it comes back to you freely and put the can on the floor. When you let go, off goes the car.

Now it's time for you to experiment. Think of a question you want answered. Like, how can you make it go faster. Will it go faster if you use different sized cans? What about putting some weight on the inside of the coffee can? Make a prediction. Then, change one thing-that's the variable-and test it out. When you're done, send your reports to our special feedback area. Be sure to tell us what you thought was going to happen and what actually did happen. Each week we'll publish a whole bunch.

Some of your Results

Amanda, age 13 of Demotte wrote:
At first, i didnt do it right. But once i figured out the problem, my can car was ready to go!

Samantha, age 13 of Wheatfield wrote:
the first time I tried this can car project, it didnt move at all. but then I found something wrong. I didnt put the rubber band in right. so once I got in in right, it rolled forever. so making this can car is so awesome.

Hannah of Victoria, BC wrote:
I took a can from the recycle, s then took some wheels from and old car toy then put some stickers and thats all

Kale, age 15 of Mason, OH wrote:
Mine didn't work at all. I tried all sorts of things to make it move, but it just sat there on the floor. Oh well. It was probably the best thing we did in Physical Science...

Clover, age 13 of Los Angeles, CA wrote:
I used it for my newton's scooter project (we were learning about the 3 laws of motion) and then everyone thinks we are going to win, because tommorrow we are having a race. It goes about 30 meters, and it only needed to go 1 meter, which was awesome!

Zykiria, age 10 wrote:
thefirsttime did not work but I did not give up I am still trying tomake It go right

Shanuk, age 8 of Edmonton, AB wrote:
i really liked the car with coffie lids and coffie cups it was the coolest

Amanda, age 14 of Plainville, MA wrote:
The first time I tried my car it wouldn't move. Then I tried a tighter rubber band and it started to work. The next time I tried it I added an extra-Beadon the rubber-band between the pencil and lid. The can now goes at least 4 meters. Also, if the car doesn't work the try a tighter rubber band.

Chiji, age 6 of New York City wrote:
it crash into a wall

Kamari, age 12 of Durham, NC wrote:
sometimes it does not work correctly

Hope, age 10 of Killen wrote:
it worked but it went vary sloe what should I do to make it go faster?

Emily, age 9 of QC wrote:
it ran for two minutes and fell off my table

Maria, age 11 of Ottawa, ON wrote:
nothing it didn't even move an inch

Brenda, age 10 of LA, CA wrote:
At firt I had A harde time geting it and iit took me five days fore me to get it good and I gote it.

Kristin, age 14 of Cincinnati, OH wrote:
it just went in a circle and fell down.

Chelsea, age 14 of Mason, OH wrote:
my car went pretty fast. to make it goe faster add a thicker rubber band. this is a cool experiment im glad my techer requeted it for our physical sciance class!!!

David, age 8 of Holm, AZ wrote:
it went in circles

Aly of OH wrote:
My class did this for a project and everybody else's can worked! My worked at first, but when I changed the can's weight it didn't really roll as far anymore!! I think I just did it wrong!! But, it was still lots of fun doing!!!

Emily, Stevi, Seth of Mason, OH wrote:
My science teacher is making me make one of these for physical science class. we are learning the coefficent of friction between the can and the floor. IT SHOULD BE SO MUCH FUN! thank you for sending this in because it is making my life easier.:]

Addie, age 13 of Salinas, CA wrote:
My can car didn't move at all when I put it on the floor!!!

Yasmine, age 12 of Chesapeake, VA wrote:
It crashed into peices.

Adrianna, age 8 of AB wrote:
weel on my can car some of the parts fell of bot it looked really cool.

Emily, age 9 of Beacon, NY wrote:
It broke once I finished it.

Michaela, age 9 of Newmarket, ON wrote:
It rolled real far but it kepp falling.

CJ, age 9 of St. Catherines, ON wrote:
I did this experiment and I had so much fun and when I tried it a wheel came of and I put it back on and it was a success!

Cecilia, age 7 of Fort Worth wrote:
When I did it I made a cardbord street for it and then I rolled it down and it worked.

Raju of Nashua, NH wrote:
I used the can car in a Newton Scooter project, and ours came 1st place! I went about 24 meters. I loved the idea and hwhoever thought of it is a complete genies.

Vahidin, age 10 of Iowa wrote:
It landed great but one wheel popped off.

Kayla, age 15 of MN wrote:
At first it didn't work, but I figured out I was winding the pencil the wrong way. Then it worked better.

Carl, age 13 of Malden, MA wrote:
I got mad at first because it didn't work but then after reading the steps more closely which is what I should have done before I finally built it. It went slow then I thought but it went far.

Alis, age 10 of Birmingham wrote:
It took a little bit of ajusiting at first, but when it started it didn't stop.

not yet implemented