Your kid says she wants to keep playing in college. Your first question is probably about scholarships, and the honest answer is there are two completely different systems and most parents only know about one.
Marching band scholarships are the wider door. Many universities, especially schools with a big football program and a marching band to match, offer band scholarships to any student who commits to playing in the band. Your kid does not have to major in music. She just has to make the band and show up to rehearsal.
These awards are usually modest, a few hundred to a few thousand dollars a year, and they stack with academic aid. The application is often just an instrument audition or a placement tape sent to the band director, sometimes as simple as a video from the living room.
Music school admission is the narrow door. If your kid wants to major in music, performance, composition, music education, she applies to the school of music or conservatory separately from the general university application. That means a formal audition: prepared pieces, scales, often sight-reading and an interview, judged by faculty who will decide if she is ready for a rigorous four-year program.
Conservatory and music school admission is competitive in a different way than marching band. It is not about whether she can march and play a fight song. It is about whether her playing is at the level required for private lesson study with a faculty studio.
The two paths are not mutually exclusive. A music education major marches in the band and also completes a full audition for the school of music. A non-music major might only ever audition for the marching band scholarship and never set foot in a music school building.
Figure out early which door your kid is walking through, because the prep is different. The band pathway page lays out what happens at each age leading up to this decision, which helps when you are trying to figure out if audition prep should start now or next year.
Talk to the band director this fall, not next spring. Directors know which schools give real dollars to non-majors and which programs run a two-tier audition process. That conversation saves a family from guessing.