They’ll be attached to street lamps and track rates of dangerous air pollution.
An additional 25 are set to be installed at other primary schools by the end of the year.
Schools are also being invited to apply to the Schools’ Air quality Monitoring for Health and Education programme.
The scheme will help teachers understand how youngsters are affected by air pollution inside the classroom.
A quarter of London’s school children are said to be affected by high rates of toxic air according to research by King’s College London.