From my experience being on the Line is so much better then being in pit or front ensemble or whatever you call it. Although you do have to work more on the Line it is so much more rewarding. In my band every1 looks up to the drumline and uses us as a guide. Being on the line is a great priveledge. Does your band have a cympal line in your drum line???? If so then that might be the way to go. The cymbal line at my school is made up of all girls and they are probably the best section out of all. It also depends on your talents and abilities as a percussionist. If you message me about the size of your line i can give you more in depth advice.

I you really love xylophone then do it, but know that you are missing out on the chance to try marching, which, in my experience most people would do if they could. the line is the elite everyone in the pit wants to be on the line and everyone in the band wants to be in the drumline too.
My advice is, try the marching, it gets better every year, you will be looked up to, and you haven't tried it yet

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plus, A girl on the line gets major respect, especially if you're good