It has been awhile since I was in the training pipeline (1992-93), however I guess by your post that you are interested in how the training program is. 'A' school and power school you sit in a classroom and the instructors come into the classroom. You spend most of the day taking notes and going over the material. Usually two or three subjects at a time. Once or twice a week you are tested on that material. 'A' school for EMs did have some lab time where we covered motor controllers, electronics, breakers, switchgear, motors, generators, etc.
Prototype is different. Thnkgs were changing as I was departing the Navy as a Staff Instructor in NY, so It may be different now. You will have some classroom time for the first few weeks for systems and radcon. Then off to work shift work. There you will have a qualification book that contains all the lessons, seminars, systems, procedures, casualties, tests, and watches that you will to complete before you go to a final oral board. This is mostly self paced, however the staff will set your goals for you. You will be required to finish x % per day or week. You will have to stand watch and learn to operate the steam plant (MM), reactor plant (ET), or electrical plant (EM) depending on your rate. You will also learn about the other areas not in your rate because you are there to work as a team to help each other and the best way to is know about his/her job also. The staff will be there to assist you in learning how it all works as well as there to quiz you to make sure you are learning what you need to. For all tasks that are required in your qualifcation book that you complete, the staff will sign your book. When all signatures are complete you will go to a final board where you will be asked to explain inrate, cross rate, intergrated plant, casualties, chemisty, and radcon principles to the board members (2 staff instructors, EOOW and Inrate Qualified). Considering you can answer the questions, you pass. On average most finish qualifing in about 18-20 weeks of a 26 week program. I believe that prototype has gone to 24 weeks total now, so the average may be different (changing as I was departing the Navy).
I hope this helps.