My son Is turning 9 Next week and he loves to read - I picked up one of these for him
http://www.ebay.com/itm/NOOK-Simple-...-/300589902031
and when the time comes that he needs to do a bit more I'll root it and it will allow him to play games/apps etc..
With Android at least there is an app called "Kids Mode" by Zoodles and it will send you reports, and lock the tablet/phone down etc..
If you Must go Laptop look into K9 Protection from Blue Coat - its free and locks the PC down pretty good