3, 2, 1 … Blast Off! Easy DIY Water Bottle Rocket
Here’s a free DIY STEM activity that is easy to do and tons of fun. At 23 / 25 points, take 30 minutes this weekend and launch your very own DIY Water Bottle Rocket with your kids! Start the activity by watching a few videos of real rocket ships taking flight, build and design your own launch pad and water bottle rocket, predict what will happen, launch the rocket and discuss what actually happened. If it doesn’t work well the first time, try again. Learning trial and error and perseverance are key. My kids had a blast. I did this 30 years ago and its still fun!
- What: Easy DIY Water Bottle Rocket
- Rating (out of 25): At 23 Points, the rating is Do IT! (Fun = 5 + Confidence & Curiosity = 5 + STEM Aligned = 5, + Time Value = 3, + Cost = 5
- Cost: Free (if you have the materials)
- Age: 3+ (recommend that parents handle the rocket and pump).
- plastic bottle – we used 1 litre, some use 2 litres
- cardboard to build your base to hold rocket
- wine bottle cork (cut in half)
- bicycle pump
- pump needle
- optional: wrap the bottle with paper to decorate. Make a point at the end with cardboard and tape to test aerodynamics. You can also decorate the base.
- Go to an open area like a park
- Fill the bottle 1/3 with water.
- Put needle through middle of cork. Make sure it’s snug.
- Connect needle to pump.
- Turn bottle over and insert in cardboard base.
- Hold plastic bottle gently with base.
- Point up and away from people and buildings.
- Pump continuously.
- Blast off.
STEM Lesson: This is a perfect experiment to discuss aero dynamics, weight, air friction and thrust. Water is heavier than air and sinks to the bottom of the rocket. As air is pumped into the bottle (air friction) it becomes compressed and eventually water will be expelled creating thrust. 3, 2, 1 … Lift Off! OK nerds, it’s also the Third Law: “When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.”
Take the activity one step further and get your kids to lead the activity at their school. Adrianna and I did this the last week of school and her Kindergarten class had a blast! Plus, Adrianna held a leadership role in her class!