Duh,

Having great instrumentation ie: Tubas, Trombones, Bass Clarinet, Bari Sax etc. contributes greatly to good pitch. Often times especially in Middle School, bands can be too top heavy or too loaded with a particular instrument (alto sax). Those instruments that are overbalanced, (ones that are higher in pitch) can have an undue negative influence on pitch.

Advice: work on switching overbalanced instruments to some of the "color" instruments like oboe, bassoon, euphonium, tuba etc. You'll be happy you did, students get the excitement of playing on a unique instrument and your HS feeder will adore you.

Steve Hendee