Teachers at 23 private schools are beginning a walk-out later over a row about pensions

Around 1,500 union members who work within the Girls' Day School Trust will go on strike.

That includes Putney, Wimbledon, Sutton and Croydon High Schools

Bosses - who say they're "disappointed" at the action - had proposed withdrawing staff from the Teachers' Pensions Scheme after the government raised employer contributions.