Originally Posted by dvh
It really depends on the teacher's own experience (plays bass also? Previously played bass?) and your own objectives (mostly theory? mostly technique?)
I am a guitar/bass teacher (I also teach mandolin, ukulele, and banjo). I feel I have a solid acumen in each, certainly more than enough for the beginner to intermediate, and lots to offer many advanced students as well. I read music and understand the technical principles of formal music education, things I insist on teaching all my students age 16 and younger (older students get a little wiggle room because many of my adults do NOT want to learn to read).
But what makes me a good bass teacher is my many years of practical experience as a performing and recording bassist. This separates me from teachers who are primarily guitarists, but can read the bass clef and walk the dog, so what the heck, may as well take on bass students too.
I think a practicing, experienced bassist can give you more pointers about things like technique and help you develop good habits (and avoid bad ones), and will have more good advice on things like gear selection and maintenance.
As far as what material you learn, go in with an open mind, and try a wide variety of styles, not just your favorites. In learning other styles, we often find a few gems that we can incorporate into our unique tastes, and we become more well-rounded musicians.