What you’ll need for a lesson
You’ll need a quality authentic instrument and bow with a case, shoulder rest, and rosin. Younger students will likely need a smaller sized instrument. Consult the instructor for recommendations on sizing or where to purchase an instrument. The wrong sized instrument will hinder progress and could lead to injury.
Strings
Gene Wie’s blog has a great summary of common violin strings. Unfortunately prices have gone up significantly since he made the post but the information is still relevant.
IMSLP
The International Music Score Library Project (IMSLP) / Petrucci Music Library has a vast amount of copyright free recordings and sheet music.