My best 5k for indoor track during college was 16:50. At the same time I ran 9:40 for 3k at a time trial. In a meet I thought I was capable of 9:20, but got injured and never found out. Anyway, a 9:20 3k is roughly 10-flat 3200. So, to go from 17:45 to 9:36 would be a big step, but I think it is doable.
Keep in mind there are many variables. I’d say 5k x-c races are slower than 5k track meets. X-C courses are notorious for being inaccurate, especially in high school. Also, keep in mind the factors that went into the 9:36. Was it hot, windy, a tactical race, etc? Look at the history of the 3200 in your state and see if 9:36 is an average time or slow or fast, etc.
Okay, now that you’ve over-analyzed everything – go out and run. Because the only way you’re going to find out is to train hard and go after it. You’re in high school. HUGE gains can be achieved just by being consistent with your training year round.