If you’re having a little trouble thinking of a good topic or if your topic is too BIG or too small, here are some things that might help.

Informative speeches usually fall into one of these categories:
Speeches about objects | Speeches about processes | Speeches about events
Speeches about concepts | Speeches about people | Speeches about places

To see lists of informative speech topics choose:
Informative Speech Topics or Good Informative Speech Topics.

For persuasive speech topics look at:
Public Agenda studies on various social issues. Persuasive Speech Topics or Persuasive and Problem-Solution Speech Topics have many possible topics.

These often list topics that are quite general so if you need help developing a focused one, try this technique.