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Science Rocks!

Build a Dam


your results

Sent in by:
Tommy of Sandwich, MA

A dam is a structure that stops a river from flowing. Can you build one out of popsicle sticks and small rocks?

Materials Needed

  • long, shallow, clear Tupperware container
  • sand
  • small rocks (like aquarium gravel)
  • popsicle sticks
  • bucket full of water



  1. Fill the Tupperware container with sand.
  2. Dig the path of a river in the sand.
  3. Choose a spot somewhere along the river to build your dam.
  4. Use popsicle sticks and small rocks to construct a dam that will let only a little bit of water come through, but not too much. Keep in mind that the deeper the water, the greater the water pressure. So, the bottom of your dam will need to support more pressure than the top of your dam. If you built your dam in a triangular shape, then the bottom will be wider and will be able to support more pressure.
  5. Test your dam by pouring water from a bucket down the river path.

How did your dam work? Did you have to make adjustments to your design after testing it? Use our ZOOMsci feedback form to tell us what you did and how it worked out. Every week we'll post a whole bunch.

Some of your Results

Brianna, age 12 of N. Attleboro, MA wrote:
i love makeing a dam it really cool

Caleb, age 8 of Goshen, OH wrote:
i built a dam in the water to slow the water down and I want to stop the water from flowing but I cant how can i???

Rodney, age 8 of Davenport, IA wrote:
When I tried to make a dam the water went threw the popsicle sticks.

Deanna, age 10 of Lima, OH wrote:
When I did the Build a dam, I used it with straws to hold the water back!!! And guess what it worked!!! why don't u guys try it on your show and see if it works.

Kayland, age 10 of Saint John, NB wrote:
the water stayed in the dam for a secent or two then the water started to come out little holes.

Haley, age 10 of Appleton, ME wrote:
well first I took some sticks and I put them in a brooke and it wasnt a strong brooke and I left it there and it wasnt knoked down yet

Aliyah, age 10 of Kitchener wrote:
when wee buit the dam it workd good YAY!! you rock

Emily, age 12 of Minneapolis, MN wrote:
We built a dam made out of sand and then we made little house to see what would happen if the dam burst. The water went over the edge and washed away all the houses. It was pretty cool.

Marcella, age 11 of Valley Stream wrote:
Water came in at first but then I added a little more sand to the project and it worked. Thank you Zoom.

Kenzi, age 11 of CO Springs, CO wrote:
it didnt work because... well... it fell apart.

Tom, age 10 of Edmonton, CA wrote:
It fell apart.

Morgan, age 8 of Indianola, IA wrote:
It didn't work. good luck.

Love, age 15 of Texas wrote:
It stop the water.

Amar, age 7 of FL wrote:
Some water broke some of the dam.

Lisa, age 10 of Battlecreek, MI wrote:
My dam held for two days then I had to cover it up because I had to move to battlecreek.

Sarah, age 11 of New York wrote:
It fell apart.

Hannah, age 8 of Machesney Park, IL wrote:
The sticks went everywhere!! It was way too hard!

Andrea, age 15 of Aberdeen, NJ wrote:
I think when you Build a Dam it makes you think like a beaver. And beavers build a dam with trees to block the river or streams.

Bonnie, age 10 of Worcester, MA wrote:
All of the water started building up behind the dam because all of the mud packed into the creveses in the wood and rocks didn't allow the water to pass.

Sydney, age 11 of Hobbs, NM wrote:
When I did it I put a lot of rocks but the water still came out.

Corey, age 9 of Ottawa wrote:
It stop the wattr from coming in.

Maranda, age 11 of Kent, IL wrote:
My dambroke I tride hanging weights from the middle and it broke in half!

Suzannah, age 11 of Dallas, TX wrote:
It sort of fell apart when I tryed to make it. But it was fun so my little brother tryed and it was perfect. It was cool

Kayla, age 10 of Sunprairie, WI wrote:
It brook down.

Justin, age 8 of Stewart, BC wrote:
It feel over when I pured the water out.

Tamia, age 9 of AL wrote:
The dam feel down, but the second time it was just right.

Marty, age 12 of Jacksonville, FL wrote:
I made one for are frot yard. It always floods at the entrens when it rains hard. It stoped the flooding. I made an invention to make the water go in a container. We loved it! We could then play out side after it rains! It was a huge one.

Sarah, age 8 of Davidsonville, MD wrote:
My dam staded up for 2 days. I made it out of sticks.

Aubri, age 12 of Twinfalls, ID wrote:
Water kept escaping through spots in the dam. So I tried different things like sand, sticks and my hand. It worked with the sand, but not with my hand or the sticks.

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