A RARE blunder by Deputy Prime Minister Julia Gillard undermined Labor's parliamentary attack on the Coalition yesterday over its opposition to Labor's $14.7 billion school building plan.

Ms Gillard, regarded as the Government's strongest question time performer, was forced to apologise after she got wrong the name of a school in a Liberal electorate that had written to praise the Government initiative.

Ms Gillard produced the email from the principal of "Milton North Primary School", to taunt South Australian Liberal backbencher Patrick Secker, in whose electorate of Barker she claimed the school was located. But after Mr Secker protested that no such school existed in his seat, Ms Gillard admitted she had mispronounced the name, which was actually Millicent North Primary School.