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Science Rocks!

Rube Goldberg™ Invention


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Complicated contraptions! Rube Goldberg designed inventions that made simple tasks much more complicated. Now you try to create one that puts toothpaste on a toothbrush in at least twenty steps.

Materials Needed

  • different things from around your house. That's the beauty of it! The ZOOMers used dominoes, string, sand, cups, clamps, balloons, rubber ducky, hammer, and marbles.



  1. Go crazy! Build the most complicated contraption you can come up with, that puts toothpaste on a toothbrush in at least twenty steps.

Did your Rube Goldberg invention take a long time to build? Did you make lots of modifications and changes as you built it? What did you use to build it? Think of another problem you want to solve Rube Goldberg style. Make a design and then try to build it. Then, test out your invention, make some changes so that it works really well, and send your results to ZOOM! Each week we'll publish a whole bunch.

Some of your Results

Kim, age 15 of St. Louis, MO wrote:
My machine worked very, very well. A pulley (a. k. a. a spool of ribbon on a pencil taped horizontally between two Lincoln Logs) dropped a playing-card box full of pennies on to a lever made of a shoe box lid. The lever lifted up my inclined plane (a book), which caused a tennis ball to roll down and hit a cup of marbles, which fell off a different shoe box and landed on the end of a tube of toothpaste. The force pushed toothpaste out on to a toothbrush. Good luck making yours!

Marisa of Vail, AZ wrote:
It was amazing! I had to get toothpaste onto a toothbrush in more than 6 steps, I got it in 7! I never knew that something could be so amazing!

Trey, age 15 of Virginia Beach, VA wrote:
It was great I made a rube goldberg machine that turns on my tv by a marble hitting the remote control.

Mariah, age 9 of Philadelphia, PA wrote:
Well it was a school project. I had to get a pencil to land in a pencil case 20 ft away! It worked! Iwas so happy!

Emma, age 6 of Brockville, ON wrote:
it worked. the gumball went in the pan.

Ashley, age 7 of Fort Wayne, IN wrote:
it worked out really great you should see it it`s cool you`ll love it i`m sure you would love it

Jesica, age 9 of Trenton, NJ wrote:
it worked. I used a string a domeno a stove and an egg and a plane cup. The first thing I did was pulling the string then the cup fell on the button to turn the stove on then the domeno fell to drop the egg in the pan then the otherstring caught the egg then the other string peeled it. while the stove was heating the string was peeling the egg. it made eggs thats how it works.

Mark, age 9 of Kissimmee, FL wrote:
The cup fell and used1 100 steps to it and it work

Danielle, age 13 of Sharpsburg, GA wrote:
For my invention, I tried to turn on my lights from my bed... it took alot of string!!!

Todd, age 13 of Mockesville, NC wrote:
It worked, 30 mardles fell into A bucket witch pulled A wire that opened a valve in a bucket of water, Witch flows down a pipe witch pours into another bucket, Witch pulls a suction cup arrow back on a bow with a push pin on the back witch pops a water baloon witch colects in a bottle witch on a lever witch closes a pair of sizzors on the arrows wire witch makes the arrow turn on the televesion.

Christian of Ames, IA wrote:
I needed my pet parrot, and a crazy rocket from hobbu lobby. Mom made me do it outside. I made a self- wiping handkercheif. As you raise the spoon of soup, it pulls a string. that jerks the ladle, throwinbg the cracker. the parrot flies aftr the cracker. It's perch tilds, making a marble roll into the bucket. that pulls a stick that pulls a string, which opens the cigar lighter, (please only do under adult supervision) which lights the firework. It shoots up in the air, which pulls a pair of scissors so they cut a string, leting the clock pendulum wich has the napkin on it which wipe your face off.

Garrett, age 12 of Dunmore, PA wrote:
I made toothpaste go on a toothbrush in 3 steps! I made a series of tunnels that a ball went into that led to a chain of dominoes. The dominoes got bigger everytime they knocked on over one. So that led to a hammer that landed on a tube of toothpaste.

Hannah, age 12 of Atlanta, GA wrote:
I made a simple device. I tied a sting to a weight (a plastic toy) on my dresser. The weight was tied to my light switch and a night stand next to my bed, so if I wake up in the middle of the night and I want to turn on the lights, I just pull the string on my night stand, which is attached to the weight and the weight falls off the dresser and causes the light switch to go on.

Anna, age 12 of Brampton, ON wrote:
I made a Rube Goldberg machine that put ice-cream into an ice-cream bowl. The first time, the ice-cream fell outside but the second time we measured how far we put the bowl from the funnel/tube so that it went right in!

Stephanie, age 14 of Los Angeles, CA wrote:
Our 8th grade final was to create a Rube Goldberg invention and link it to history and our english classes. For history we incorporated women's movements in history for every Rube Goldberg step, and a metaphor for the english part. It was alot of hard work because it was only my friend and I but in the end, watching it all work out it was loads of fun!

Ross, age 7 of Hinckley, OK wrote:
I built it in my livingroom I pulled a string it pulled a track out of the way of a ball it rolled down a book it hit a book whitch pulled a string and pulled a book and it hit a book and pulled a string it moved a pen out of the way of a marble and rolled down a track and into a box.

Rachel, age 8 of Scappoose, OR wrote:
I dropped it when I brushed my teeth, and it worked! With a needle, some thread, a plastic egg, and a wieght, it squirted out tooth paste so I could brush my teeth!

Henry, age 10 of Montclair, NJ wrote:
I used some marbles, cups, toys, rulers and oter stuff and had a wieght drop on the toothpaste and it squirted on the tooth brush.

Cristen, age 15 of TN wrote:
I made my radio turn on! Well I open the door then the door pulles on a rope which makes a ramp go up and move a car and the car goes down the ramp... and then the car lands on a spring that make a ball hit the raio "on" button! It was awesome!

Ross, age 7 of Hinckley, OH wrote:
I turned on my rotating dart board. I attached a string to it, and it pulled a string which lifted a book, which let a car roll down it. Then the car hit another car with a switch that turned on. It moved forward into an elevator and up the elevator, and it hit some dominos. The dominos hit a toy man which hit a marble which hit a can which rotated and hit another marble down a tube contraption. Then the marble hit a car with a pencil attached to it, the car rolled up to a balloon and popped it with the pencil. It really will be cool when I build it. So far, I built the part up to the top of the elevator.

Auburn, age 13 of Douglas, GA wrote:
My school assignment was to creat an invention that made the light turn off from the bed, so when you got in bed you could turn the light off from there. I pulled a string that lifted a cup. Then I cut the string and the cup flee and started a dominoe chain reaction the last dominoe fell on a string and trigered a big toy car. The car roled off the dresser and hit a popsicle mini see-saw. on the other end was a smaller car. The drop made the car jump. It went up, and when it came down, it hit the light switch, turning it off. It was so complicated that it took two weeks. But in the end, it was fun to watch!!!

Bryan, age 13 of OK wrote:
I pulled a string connected to a dominoe, which had another dominoe on top of it, thus triggering a chain reaction in which the dominoes fell in a row across my dresser which hit a small book of cards which fell and hit a car tied to a string which was tied to a lamp so the car swung and hit the light switch and turn off the light.

Sarah, age 8 of Atlanta, GA wrote:
I tried it but it didn't work. what was saposed to happenwas this: I hit a train of falling daminose which hit a ball which hit a cup tower and the bottom cup was taped to string wich was attached to a book so the book was saposed to fall and sqeeze tooth paste on a tooth brush.

Kati, age 14 of Boise, ID wrote:
Well first I kicked a ball into a cup which was attatched to a wheel and axel. Then the wheel wound up a string attached to a pulley and when that string got tight enough it lifted up a lever that hit a platform with a spikey ball on it and the ball rolled down a ramp and popped a balloon at the end!

Kaila, age 13 of Lexington, TX wrote:
I was assigned this project at school, and we had to build one that launched an egg! It took a really long time, we also experienced some difficulties! It took about 2 weeks!! What happened was, a ball rolleddown a ramp, knocked over dominoes, went through a hole onto another ramp, knocked into some bells, down a tube, and onto a mousetrap, which released a spring that had a tennis ball on it, the egg launched 20 feet!

Shamikh, age 8 of Irving, TX wrote:
My invention was to make a cup of water pour into a bowl. When rock falls on the scissors, it is going to cut the string, which is going to make the stick fall on the cup of water. The cup falls and the water pours into the bowl.

Nikkie, age 13 of Belleville, ON wrote:
I pressed a button (two waterbottle lids facing one another) through a cardboard sheet, hitting a golf ball, sliding down a track, landing in a cup attached to a teator totter, allowing the cup to lower with the extra weight of the gold ball, until it hit the ground, the cup dropped, the gold ball going down another track, falling onto the bottom of a waterbottle, filled with water and the cap lightly screwed on, and now the gold ball hits off the cap and the water hits another sheet of cardboard so it can lightly water the plant!

Landon, age 11 of Macon, GA wrote:
Well, when I tried to do it the first time it didn't work. This is what happened, when the hammer hit the tooth paste it exploded, so I tried a smaller hammer and it worked perfectly.

Alex, age 11 of Wallington, NJ wrote:
I made a wake up machine it worked great!!! I used a rubber duck, string, dominoes, water, and a cup full of sand!!! I got really wet if I fell asleep!!! I think this idea was great!!

not yet implemented