Lambeth Academy excluded more than 20% of its pupils in the 2017-2018 school year.
The latest Department for Education exclusion figures show that the school handed out at least one fixed-term exclusion to 21.7% of its pupils in in 2017-18, the most recent year for which figures are available.
This represents the highest fixed-term exclusion rate in south London, and the third highest in the capital.
A spokesperson for the school said the rise in the exclusion rate in the 2017-18 school year was ‘temporary’ and coincided with the introduction of a new behaviour policy which ‘resulted in behaviour improving across the school to the benefit of every student’.
The 2017-18 year saw the fixed-term exclusion rate rise for the fourth year in a row.
A fixed-term exclusion involves a pupil being suspended from school for a set period. Last year, nationally, the average such exclusion lasted two days.
The fixed-term exclusion rate at the school was more than nine times higher than the national average rate of 2.3 per cent.
A Lambeth Academy spokesperson said the data provided for the upcoming set of DfE figures for the 2018-19 school year shows a fall in the exclusion rate to three per cent.
The spokesperson added: “The overwhelming majority of parents and students have been supportive of the behaviour policy, even at the point of its introduction.
“Exclusions continue to fall whilst the school maintains its focus on ensuring that all students, including those with special educational needs, are able to enjoy disruption-free learning.’’