That'll Teach 'Em is a British reality television documentary series produced by Twenty Twenty Television for the Channel 4 network in the United Kingdom.

Each series follows around 30 teenage students as they are taken back to a 1950s/1960s style British boarding school. The show sets out to analyse whether the standards that were integral to the school life of the time helped to produce better exam results, to the current GCSE results and to compare certain contemporary educational methods with modern ones.

As part of the experience, the participants are expected to board at a traditional school house, abiding by strict discipline, adopting to 1950s diet and following a strict uniform dress code.

After four weeks, the students then take their final exams, produced to the same standard as contemporary GCE O Levels.

There were three series of the show, the first airing in 2003, the second in 2004 and the third and final series in 2006.