Use your knowledge of mass, volume, and density to pick the material for a bike. There are four main materials used in bike manufacturing today: steel, aluminum, titanium and carbon fiber. Research three of these materials (titanium, steel, and aluminum) and decide which one you would use to make your dream bike. Base your decision on three factors:

1. Weight
This will depend on how you will use your bike. If you are planning on racing your bike then you want it to be light. If you are just going to use it for transportation, weight is not as important.

2. Strength
The strength of the different metals is called tensile strength. It is measured in units of kilograms per square inch (ksi). A stronger bike will last longer and be more durable.

3. Price
You have $1,000 total to spend to get the frame, the components (wheels, shifters, gears), and extras (bags, lights, locks). If you spend more on the frame, you will have less for other stuff.