<p>The fragile double reeds of an oboe will not be able to hold up in a marching situation!</p>
<p>If she is not a serious oboe player, she will find it fun and trivially easy to switch to a clarinet or saxophone. (If she ever played a recorder or flutaphone when she was a kid, a sax has similar fingering and she can learn to play music written in the key of C in about an hour, I swear.) If she is a serious oboe player, playing a single reed instrument can be hard on her embrochure and she should go for the glockenspiel - that is what the oboe players in my D’s band do. (My D plays bassoon in wind ensemble and sax in marching band, but she is not exactly a very serious bassoonist.)</p>