Purplemath: Here are online notes about writing numbers in scientific notation.
Gomath: Here are online notes and practice problems on scientific notation.
Link Name: link description and/or student directions (on page or download file)
ExploreLearning: Students can self-enroll but need to get the enrollment code from their teachers. Teachers have to assign the Gizmos to their classes. Students should read the Exploration Guide. An online assessment is provided.
Larson´s PreAlgebra: This is server-based software and students must be logged into the server to use it. Also, students need to be enrolled by their teachers. Click on the Place Unit Title Here, then click on Place Objcetive Title Here. Do the See It, Try It, and Zap It.