The discount is defiantly worth it. When I was in school I had saved up enough money to build a nice sized starter set, with a box on sale from Craftsman for the tools to sleep in. As you go through classes make note of the tools you use the most, and put them on your “wishlist” so to speak.
I know some tools you aren’t allowed to use the discount on, and the 50% off can give you a head start on the basics. But don’t expect to be able to not need things from the various trucks that will stop by the shop in the field.