Not just laptops
If this is the same scheme I worked on, Its not just laptops, there is a 24/7 support arrangement with a Becta approved supplier, plus the laptop comes with a standard software stack, office, AV, anti-spyware etc plus monitoring software (Securas) as these are designed for education not playing half life.
There is also the not so little amount of money required for the ADSL provision (for those that don't already have it) and the remote access solution, they are forced to use a software vpn that provides filtered Internet access and access to local (school) content only.
At the end of the day, the money is peanuts is it helps the kids to fullfill their potential and yes, some will undoubtably end up on eBay, but when prison places cost 40K a year and top rate tax payers are paying 45% back to UK PLC it sounds like a bargin.
Incidently some of these are going to home schooled kids who can't get into a regular school and others to kids in hospital long term so they can continue their school work. The alternative would be to exclude them from schooling altogether or pay 30K for a teacher per student.