Grizzly Ape is a software development company in the U.K. that has built some handy Firefox add-ons. One of their free add-ons is Screen Draw.

With Screen Draw installed you can type on and or draw free-hand on any webpage that you’re viewing in Firefox. You could circle elements on a page then type a bit about that element. Your screen drawings can be saved as PNG and JPG files.

Applications for Education
If you’re looking for a quick way to create annotated screen images to provide directions to students, Screen Draw could be a handy tool for you.

One way that you might have students use Screen Draw is to have them practice giving written directions. Have students pick one of their favorite websites and write directions for using it as if someone was brand new to using the web. Students (and teachers too sometimes) often assume a lot when giving directions. By starting from scratch assuming that the audience knows nothing, students are forced to slow down and think about the details that they might otherwise assume everyone knows.

For some more screen capture options, please see 7 Good Screen Capture Tools for Teachers.