So, you've already got a few extract batches under your belt, and the time has come to make the leap.
Making The Leap covers the basics of all-grain brewing, the equipment needed, and the math behind it. The class lasts around two hours. (Note: since the boiling process is the same in extract and all-grain methods, this class does not cover the boil. It discusses the all-grain process up to the boil, including preparation, the mash, and sparging.)