I took three courses in a gym, the first was the starter course (how to top-rope belay), the second was how to lead climb, and the third was how to climb multi-pitch. All courses were great, but the instructor for the lead climb course was exceptional. As you get into climbing more and more, I do reccomend more advanced courses, because you get to learn from experts in the craft, and they get to share their passion with you. Its educational and inspirational.