Ouarada Ahmad, who taught at the Prendergast school, Lewisham, south London, was found guilty of unacceptable professional conduct by England's General Teaching Council. It heard she claimed housing and council tax benefit between January 2002 and February 2004 and jobseekers' allowance for nine months while she was working.
Mrs Ahmad was sacked from the girls' secondary for gross misconduct despite claiming her actions did not amount to fraud, and it later rejected an appeal.
She told a school disciplinary hearing she had had childcare difficulties and that her husband had to have an operation in France which cost Pounds 3,000.
The GTC heard Tower Hamlets council agreed she could pay a pound;1,200 penalty rather than be prosecuted as she was her family's bread-winner and had co-operated fully.