We just got in some new combination cables for the classroom. We have had 15 footer combination VGA and 3.5mm audio for teachers, but now C2G (formally Cables To Go) does a nicer 25ft length. The metal screws on both sides really helps anchor the cable vs. the other models that have plastic coating.
I like the longer cables with a dock cleat so teachers can have flexibility in the room with cable slack while still not having to require software-based solutions. The dock cleat solution I put in the rooms a couple of years ago seems to be working well.