I think updating a site is more important on a kids' site. We've found we get more repeat visits on the kid-oriented sites. We even get email from kids asking when we're going to add more stuff. So that helps to prompt us along. Adding new stuff also offers more chances to spark someone's interest.
Different people learn different ways.
Some want interactivity, some want to just read, and some just want to see something on the screen. By constantly updating the site, Spadaccini hopes to get kids' interested somewhere along the way. Wirth previously worked on Brainsurf , a site with a primary audience of junior high and high school students. Brainsurf was used in classrooms to introduce kids to neuroscience, which is the study of the brain and nervous system. Wirth says she learned a lot by working on Brainsurf, especially about what she'd do differently.