This is a really fun activity for starting to learn about properties of materials and the effect of gradient on speed. We split the experiment into two parts, first we tested different materials to see which worked best as a boat and then we raced the boats down different inclines.
This activity is also part of my Playful Science series, do don’t forget to check out the rest!
Which materials make the best boat?
Materials
Paper
Optional pirate decorations
Corks
Elastic bands
Skewers
Black cardboard
Wooden lolly sticks
Washing up sponges
Plasticine
Glue
Anything else you want to try
How to make mini pirate boats
Construct your boats using your different materials.
We made a lollystick raft, a simple boat with a washing up sponge and a paper boat.
The paper boat worked well at first, but as it absorbed the water it sank.
Our tub boat wasn’t stable enough and fell over. I think we needed a shorter sail.
The raft and washing up sponge floated well, but both were a little too big for our half pipes, so we decided smaller washing up sponge boats would be the best option. These were the perfect size for our pipes.
Another idea is to use corks. We fastened three together with an elastic band and added a sail.
Racing pirate boats
Next we set about investigating whether the incline of a slope affected the speed of the boat. We used the sponge boats for this, just because they were the most stable.
What do you need to keep constant?
Type of boat? Do they weight the same?
Amount and force of water – is this hard to keep the same?
Variable
Incline
Which do you think would be the fastest? How can you measure which is the fastest?
We released the boats at the same time and watched to see which reached the bottom first, but you could do them one at a time and record the time taken for each to reach the bottom from the top of the pipe.
Other Ideas
Use a straw to blow the boats across a calm surface of water, what happens when you blow gently and then with more force? Does the boat move faster if you blow the air close to the boat or far away?
Can you use the straw to create waves across the water?
Suitable for Early Learning Goal 16
Exploring and using media and materials
They safely use and explore a variety of materials, tools and techniques, experimenting with colour, design, texture, form and function.
Key Stage 1
Everyday Materials
Uses of Everyday Materials
Working Scientifically

Last Updated on July 16, 2021 by Emma Vanstone
I love your website. Thank you for posting all your ideas. This pirate one looks so fun- it is on the list of things to try this summer!
Hi, great ideas and love the added questions to encourage their inquiry skills. I was wondering what the green stands are that are holding up your 1/2 pipe ramps? Plant cages? Also, did you buy the pipes already cut? If so, where? Thanks 🙂
Love the Pirate Ship made from a cup.
Does the sponge one work? Or does it suck up the water and sink?