As far as classes here in Marion County we already started the Master Gardener program, which goes on Mondays from early January through mid-April. We offer those classes once per year, so unfortunately the next offering is in January 2017. If you would like more information on those classes, please feel free to contact me directly.
The Master Gardeners offer workshops regularly through the year on a variety of topics, often in their demonstration garden, the Marion Garden. Check the MG webpage for more information:http://extension.oregonstate.edu/marion/master-gardeners
Another opportunity if you are looking for online classes is to check out OSU Professional and Continuing Education for gardening classes:
Feel free to contact me directly if you have additional questions.