In high school (8 yrs ago)..., I played high F# and G (above High C) Consistently, but now my max is about High E above High C... I need to practice...
I have a Double High C Method book by Frank Minear... It works. (I just don't have time to play anymore)... Frank played with Stan Kenton for a while... He's gone to heaven, but his son is my friend and gave me his personal method study book.
In my junior year, I hit the G above high-C, but now I'm playing the F-F# pretty consistantly. It all depends on how I'm feeling. Playing high is dependant not only on ones own ability (but that will be the limiting factor to yur max), but also on whether or not you believe you can play that high.
i can play a F above top c, but to be honest. thats the highest you ever need to be able to play, think the highest note iv had in a piece is hydens trumpet concerto and thats an Eb above top c and thats a grade 8 piece. trumpet playing isn't all about playing stupidly high notes (it is fun tho) its how well you play those stupidly high notes. but thats my opinion