I think that this is common and is basically developmental.
Education.com has many activities and worksheets that you may enjoy. I've also included a link to STARFALL, a great online program that is child friendly and if you have access to computer with internet in the class, you may want to allow them to work freely on this site. Our Kindergarten class uses it daily.
Before allowing the children online, I would first get a signed consent form from the parents.