I needed to get an academic waiver when I came through for pretty much the same reason. Also I initially joined on an AECF contract, but switched when I got my nuke contract a few weeks later. Pushed my ship date back some, (about six months, actually) but I got the contract. Waivers are relatively easy to get, that's more big navy stuff. I'd definitely put the petal to the metal in high school though, working on your study habits now will give you a head start in A-school. I had never studied through high school, and was a pretty lazy student. When I got to Charleston I really had to learn how to have an academic work ethic. You put a lot of work into learning, odds are more than you've been used to. Best of luck with your naval future, if you have any questions feel free to message me on here. I love talking to new sailors and I'm currently finishing up my last leg of training at Prototype in New York. I should have some of the most up-to-date information on the training pipeline from a student's perspective.