Schools designated as polling stations are grappling with the problem of how to accommodate exam candidates as well as the electorate.
On the day, thousands of nervous students will sit GCSE English and geography and A-levelAS-level French, history and maths.
At one Birmingham secondary, the whole of Year 11 will have to be accommodated under exam conditions but part of the site is out of commission because of election day.
And the prospect of members of the public wandering the corridors in search of the polling booths could cause invigilators a few headaches.
Thousands of schools - mostly primaries - will close on June 7. They have traditionally been chosen by local-authority electoral offices because they are local, accessible and free.
Moves to use buildings such as supermarkets and libraris have gathered pace but in many constituencies, such as Education Secretary David Blunkett's Sheffield, schools will again be the main venue.
Since Mr Blair made his announcement at St Saviour's and St Olave's in south London, it seems schools have become fair game at the hustings. One headteacher was forced to declare his school a politics-free zone after a candidate was spotted handing out leaflets to parents in the school car park.
Randall Lewis, head of Roundhill primary, Nottingham, said that the Conservative parliamentary candidate, Pauline Latham, was capitalising on a ready-made audience and compromising the school's neutrality.
Mrs Latham, a former chairman of the Foundation and Voluntary Aided Schools Association, said she thought she was standing in the car park of the public library.
She said: "Tony Blair disrupted a school and used it for political purposes when he announced the general election."