Why take the Titanic Challenge?

By designing and creating your own boat, you and your family will learn about some principles of geometry and engineering. As you test how much weight your boat can carry, you will learn about scale, measurement and volume.

At what point will your boat sink like the Titanic? The Titanic was a huge boat designed and built at the start of the 20th Century. Although never officially called an ‘unsinkable’ ship, it sank on the 15th April, 1912 after hitting an iceberg. 

Watch Byron introduce the Titanic Challenge.

Connections to real life

Builders and engineers apply maths skills to all of their boat designs, including canoes, life boats, speedboats and cruise liners.

One of the most well known marine architects in Australia is Ben Lexcen.  He became famous for the winged keel design applied to Australia II,  a yacht which won the prestigious America’s Cup in 1983 – the first non-American yacht to win in 132 years.

1. Setting the Scene

Using some common household materials, build a boat which not only floats, but also carries weight. For this, your family will need to focus on design of the hull (the bit of the boat that sits in the water). By planning, designing and communicating effectively as a team, can you stay afloat?

Maths words

buoyancy – an upward force exerted by a fluid that opposes the weight of an immersed object.

estimation – an approximate calculation of something.

mass – a measure of how much matter is in an object.

Find more maths words in the Glossary.

2. The Challenge

Build a boat and test how much weight it can carry.

1. Gather your construction team. You may want to involve a parent, grandparent, brother or sister, or family friend.

2. Collect the following: a ruler/tape measure; materials to build your boat (e.g. sticks, wood, empty bottles or corks – you can use just about anything that will float and not get soggy); and some sticky tape, string or glue to stick your boat parts together.

3. Clear some space and use your team skills to build the best boat you can in 30 minutes – it should be no bigger than 30cm long by 15 cm wide by 10 cm tall.

4. Collect some objects you can use as known weights to put in your boat to test how much weight it can take (e.g. coins, some metal spoons or a tin of tomatoes).

5. Each team member should estimate how much weight s/he thinks the boat can hold and guess whether the boat will (a) sink or (b) capsize. Write down everyone’s estimation before you test your boat.

6. Find somewhere to test your boat (e.g. a sink, bucket, bathtub or esky). Add weights and test how much weight your boat can carry before it sinks or tips over (capsizes).Remember, not too heavy to start with!

7. Capture images or video of your boat.

8. Reflect: what was the maximum amount of weight your boat managed to hold before sinking or capsizing? Discuss with your family if you think you should have used a different shape for your boat.


If you are stuck, here are some suggestions that might help.

When estimating how much weight the boat will hold, you will need to use items that you know the weight of. If you have some kitchen scales you could weight each item you add to your boat. Otherwise try using tinned food items which have a weight printed on them or coins (you can use this website to find the weight of each Australian coin).

When you are designing your boat, don’t forget to check out the strategies section of this site where you will find information about prototyping and planning.

To find out more about the hull shape of different boats have a look at this link.

3. Keep Going

Grab five to ten items from around the house and get family members to guess which ones will float and which ones will sink. Write down the guesses and see who guesses the most items correctly. Remember to only use waterproof items or items that won’t be affected by getting wet. Some suggestions for items to test:

  • Fruits: apples, bananas, mandarins, oranges
  • From outside: Sticks, leaves, rocks
  • Assorted household items: waterproof keys, coins, forks and spoons, pots

What makes a good estimate? Having a good idea from past experience helps you to make good estimates. The more you experiment and the more data you obtain about the world around you, the better educated your guesses become.