Pupils from Hall School, Wimbledon joined presenter John Craven and the Countryfile team recently, to take part in the OPAL climate survey.
They also demonstrated a number of weather experiments, including creating a tornado and a cloud in a bottle.
See a short clip of how they got on the BBC website.
OPAL was helping promote a new BBC series called The Great British Weather which starts this Wednesday at 7.30pm.
Take part in the OPAL climate survey
By making simple weather recordings you can help scientists learn more about our climate. The OPAL climate survey is open to everyone and you can download everything you need to know from this website.
More than 1,800 people from around the country have already submitted their results. Take part today and add your findings to our results map.