The small print also suggests the subsidy is less straightforward than it appears. For a start there is the lottery element:teachers have to buy a computer before they know how much money they will get back - if any. Then there is the clawback: those receiving pound;500 for a reasonable laptop will pay most of it back to the Government in income tax and VAT.
More imaginative responses are needed from Government and the education service as a whole. The same money spent by a governing body or local authority on laptops for its teachers is not subject to either of these taxes and bulk purchases would provide economies of scale as well as encouraging compatibility of software and hardware.