Your HW assignment for today is to write a four-paragraph essay about rubber and plastics. The first two paragraphs should have 3-5 sentences each, and should explain what rubber is, what natural sources we get rubber from, and the things we use rubber for. The last two paragraphs should explain what plastics are, how we make them, and the things we use plastics for.
One of the best sources for this assignment is wikipedia, which is a great starting place. It will certainly give you a good definition for "rubber" and "plastics." It should also show you how we get these substances, as well as how they are used to make things around the world!