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Sent in by:
Alexander of Alexandria, VA

Make a machine to measure movement.

Materials Needed

  • cardboard box with the flaps cut off
  • plastic cup
  • felt tip marker
  • string
  • cup of small rocks, marbles, or bolts
  • clay
  • paper
  • scissors



  1. Do you know what a seismometer is? It's a machine that shows earthquakes or other movement. Here's how you make a really simple one that can measure movements that you make in your house.
  2. Check with a grown-up before you begin. Cutting a cardboard box can be pretty tricky.
  3. First, take a box and open the top. Cut off the flaps and turn the box so the open side faces you.
  4. Using scissors, poke two holes next to each other in the center of the top of the box. You may want to ask an adult to help with the scissors.

  1. Poke one hole in the center of the bottom of the plastic cup, one hole along the rim of the cup, and another hole exactly opposite that hole.
  2. Put the marker through the hole in the center of the bottom of the cup. The writing end should be sticking out of the bottom of the cup.
  3. Put some clay around the hole so that the marker won't move.
  4. Cut a 45cm piece of string (although if you have a bigger box, you may need a longer piece) and thread it through the two holes along the rim of the cup.

  1. Then, thread the string through the holes in the box, so that both ends of the string are equally in the box. Tie the ends on top of the box.
  2. Fill the cup 3/4 of the way with something that'll weigh the cup down. You can put anything in the cup to weigh it down-marbles, bolts, rocks, anything heavy will work.
  3. Cut a strip of paper that's as long as the box and approximately 5 inches wide.
  4. Put one end of the paper under the marker. Take the cap off the marker and make sure that it sticks out of the cup far enough so it touches the paper.
  5. Now have someone shake the box right and left while someone pulls the paper forward. If you do this right, you should get a squiggley line on the paper.

The more you shake the box, the wider the lines will be. Try pounding on the table and see what kind of lines it makes. Try making some changes to it so that it can detect really small movements, like singing or talking softly. You could also try making the holes in the box closer together or adding more weight to the cup. Be sure to share what you've learned with other ZOOMers around the country.

Some of your Results

Caitly, age 12 of Durban, South Africa wrote:
My siesmometer turned out pretty well. I think I learned a lot.

Natalia, age 12 of Chicago, IL wrote:
First my teacher said to do this for homework so I did than when I began it was kinda hard but I got the hang of it! Its really cool!

Jazmin, age 11 of Chicago, IL wrote:
Its so exciting I loved it.

Leah, age 13 of Appleton, WI wrote:
Like usual, I didn't start my project until the night before it was due but this was a really fast and easy way to make a seismometer and it was a great learning experiment! So neat!!

Nathan, age 11 of Perris, CA wrote:
dear zoom, it did not work at first but when I put string side to side so now it work thank zoom

Jasdeep, age 13 wrote:
awesome... helped a lot with my school project thanks

Sammy, age 9 of New York, NY wrote:
It was so cool. It actually worked. It was moving and it made a scribbly line. It was for my class project about, "how things move."

Zoom Fan, age 14 of Windsor, ON wrote:
well the first time I tried it, it didnt work i found out why later... the box wasnt sturdy enough so I made it sturdy and the string kept falling of so I taped it. and it worked

Tori of Kitchener, ON wrote:
We needed to build a seismometer for earth and space. I was totally not into the whole idea of building one, but then I found this website and was like "Score!". this is easy and quick to build and it works.

Aelya, age 12 of Lewes, DE wrote:
this experiment was so cool! I presented it in Ancient Civilizations class and everybody thought it was awesome. We put the box on different surfaces and saw how different it was everywhere. It was alot of fun! Thanks for your help ZOOMers!!!

Joy, age 12 of Citrus Heights, CA wrote:
It's sooo frustrating! is the cup suppose to hang and swing? or stay still?! and the cup keeps leaning back and stuff! is it suppose to?!

Markus, age 6 of Gold Coast, Au wrote:
It moved when I moved the top of the box. the texter movved making the lines on the paper. I liked this experiment.

Alex, age 8 of Gold Coast, AU wrote:
The result was that on the paper was how big our pretend erthquake would have been. great experiment.

Danielle, age 11 of Mass wrote:
Hi zoom. Well when I made my seismograph, it was kinda hard at first but then I understood it more, then it worked out perfectly. well thanxxxxx!

Myob wrote:
It worked.

Angel, age 11 of Dahlonega, GA wrote:
Well, me and two other friends had to do a seismograph for science. My friend had remembered about one she'd seen on the show so we checked and there it was a perfect idea!! It took us about one or two hours to build, but it was worth it! We haven't shone it in class yet, but it works and we are very glad. It was simple and a great idea!! THANKS ZOOM!!!

Katelynn of Haddon Township, NJ wrote:
I had no idea that there was so much vibration at my house. I made it for a extra credit report.

Michael, age 13 of Zebulon, NC wrote:
It did exactly what I thought it would do.

Christian, age 13 of Lexington, SC wrote:
well it didnt work out how I planned but it works.

Celaya, age 11 of Tustin, CA wrote:
it didnt work at first when I shook the box then I used a reciet paper and used then pulled it from the back of the box so that the pen would move

Alejandra of Baldwin Park, CA wrote:
It was Rreally Cool because at first we tried moving the box but it did not work. Then my friend started to move the desk and it caused vibrations and viola it worked!

Sa'Von, age 13 of Michigan City, IN wrote:
Well, for a moment it wasn't working becuse I didn't have enough pressure on the marker. So I added more marbles to add additional weight to the marker. Then it started to make little zigg zagg movement.

Meredith, Kindall, and Destiny of AK wrote:
The first time it went in circles. Then we pulled on the string to lift up the marker and it went really good. We did it 8 times most just for fun. We had lots of fun doing this project. P. s. you should do it.

Breanna, Megan, and Chantal of AK wrote:
At first it didn't work because the pen was to big and then the sting broke. Then we got a smaller pen and got a new piece of sting that we made tighter. When we were done we tested it and it worked perfectly. P. S. It was the best earthquake ever!

Hunter, Brian, Wyatt, Cody of AK wrote:
Ours was one of the best in the class it took a few times to get the pen to the right hight to have it make a good mini earthquake it worked good.

Nada, age 16 of Taif, Saudi Arabia wrote:
I wanted an idea for a science fair project of my school so I searched for it in Zoom website. I thought that the seismometer would be a great project so I made it. And used a dozen of glass marbles for the weight and used a liquid ink ball pen, and took the readings on a graph paper it worked perfectly! And I even got a prize and a certificate for it!!!

Georgina, age 9 wrote:
It actually worked I made a mini Earthquake on my desk!!!

Whittney, age 12 of Salyersville, KY wrote:
I did it in a science fair and I won. It turned out good. I even put it outside and it maid a little line but over all. I loved it.

Noami, age 13 of Tucson, AZ wrote:
When I did my project it worked really well I learned how a seismometer works in real life and how you could make one by yourself. Thank you or the great idea!!

Brookelynn, age 9 of Blackfoot, ID wrote:
I had fun making the seismomenter whean I shook it made all kinds of designs it was cool.

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