They called on Tory education secretary Michael Gove to resign.
Parents and children from Roke School in Croydon and Gladstone Park School in north west London joined them.
They are fighting plans to turn the schools into academies.
A delegation of civil service workers from the PCS union, who were set to join a 250,000-strong national strike on Wednesday of this week, joined the protest too.
Members of the NUT’s national executive committee addressed protesters.
They talked about possible joint strikes with the NASUWT union. But protesters took up the chant of, “Strike, strike, strike!”
Teachers from across the Midlands also demonstrated outside the Department for Education offices in Coventry.
The Tories are destroying the education system as we know it and the clear message from the Midlands is “Gove Must Go”.
Over 70 NUT members met at the end of the lobby holding placards to demand that our union executive call immediate and escalating national strike action in response to these unprecedented attacks.
Chris Denson, joint secretary Coventry NUT
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