From the department of reinventing the wheel, here are newly cleaned up versions of some charts I like to use with young brass students. Linear fingering charts that start at the "lowest" note and end at the "highest" note are essential for quick reference, but at the cost of obfuscating the actual design and function of the instruments. Vertical charts, meanwhile, are more transparent in this way and thus are essential companions to (not substitutes for) the linear ones found in the back of every band method book.
Though the advent of Google Images has made free materials of this type from around the world almost perfectly accessible, I've never found anything quite to my liking in this particular department, so enjoy my latest contribution to the content-rich life.
The generic treble clef version is potentially important for tuba and euphonium players who, even as casual high school band members, probably will not be able to completely avoid encountering transposed treble clef parts for their instrument. It also is a useful prop in an introduction to writing for brass instruments, though it must in that case be emphasized that the horn is a brother from a decidedly 'nother mother.
PDF files can be accessed here:
Treble Clef Brass
14 January 2015
10 January 2015
I just saw a Craigslist post for a $9/hour security job that lists "critical thinking" as one of the required skills. Evidently it is not a required skill in the HR department.