My kids know that when I call them over to the computer, it is usually BrainPOP time, they watch the 'movie', and then do the activities!  It is an awesome site, full of information on all school subjects, very well organized and thought of. We actually subscribe to all three options they offer - my kids are 1st and 3rd grade, but usually look at the 'older kids' version as well. Here's how it works: You select a subject, then a topic, the kids watch the short video, and then there's activities to follow, such as printables, online games, even jokes! All related to your topic... They even have parent resources for how to make further use of the information...BrainPOP even offers a free trial, I do hope you check it out, it has been a great addition to our homeschool curriculum!