Bottle Water Fountain

Create a water fountain or drinks dispenser that works on demand – just by screwing or unscrewing the bottle lid!

This water bottle air pressure activity is a fun way to learn about how molecules, gases and vacuums.

It’s a great engineering challenge too – just set your kids the task of filling containers without pouring water out of the top of the bottle, and see what ideas they come up with!

We’re excited to share this activity by Milena from Peque Creativity. Check out the full instructions below!


All you need for this easy water bottle STEM activity is:

  • disposable plastic water bottle
  • straws
  • playdough (optional – see instructions)
  • sharp scissors or other tool to make small holes in the bottle (an adult should do this or supervise heavily)
water bottle air pressure activity at home


Here’s how to do this water bottle fountain activity at home:

1. Take a plastic bottle and make 3 small holes in it. The holes need to be as close to the width of your straws as possible.

2. Insert the straws into the holes.

3. Place the bottle in the sink and fill it with water. Water will come out of the straws!

4. Screw on the lid – you’ll notice the water stops flowing.

5. To get your drinks dispenser or fountain working again, just unscrew the lid.

If you have water leaking around the holes, you can add some playdough to seal the area around the straw and stop water from escaping.

How does it work?

Even though we can’t see it, air always takes up room. The water bottle is mostly full of water, and the rest of the space is filled with air.

The water bottle needs to be filled with something – if it is completely emptied of air or liquid it will collapse. 

When the lid is tightly screwed on, no air can enter to replace the water leaving the bottle through the straws, so the water stays inside the bottle. 

When you unscrew the lid, air is able to enter into the bottle to fill the space that the water was taking up. That means the water is able to come out of the straws – and that’s what makes your water bottle fountain work!

Thank you to Milena from Peque Creativity for this fun STEM activity idea! 
You can discover more of Milena’s activities here.

If your kids enjoyed this activity, we think they’ll love making magic jumping foil too!

magic jumping foil activity for static electricity demonstration