As part of a master composting class I created a composting and computer science lesson plan. It teaches composting, and then includes a project where students create an arduino powered device to collect temperature and moisture levels of a compost pile (or anything, really) and then send it to a web application they create. Instructions, materials, and source code for everything is here. There are tons of ways it could be improved, as it was only designed to teach concepts. My plan was to leave it here and move along to another project, but I figured there might be some folks out there that want to collaborate make it a more useful monitoring product!