Contribution to the powdery mildew citizen science scheme has recently been added as an optional activity for GCSE teachers to involve their students in. I have managed to collaborate with Alistair Moore of University of York Science Education Group to include this in the teaching resources of Science and Plants for Schools (SAPS).
This will be one of many great new ways for school students to get involved with important aspects of the natural world around them. Amongst others, SAPS also offer practicals on plant disease detection and tree health.
Have a look at the powdery mildew resources here.