The difference between the two views is that we are using different processes to record. For example the student activity screen takes into account if the student has multiple browser tabs open in Buzz at the same time. If it didn't do that the time would be inflated.
Thanks for your quick response... Does that mean that if a user has Buzz open in two different tabs, it counts their activity time double?
In the grade editor it will show an inflated time for multiple browser tabs open. In the student activity screen it will display less time taking into account for the extra browser tabs open in Buzz.