Let me start of by saying: Great samples! I wish I had those. The beginning was a little bit bland because of the lack of harmonic variety, but then you start to change it up a bit, which is nice. You wouldn't happen to be the soloist would you
? Oh, so this is string orchestra. I love the big full sound you achieve in the middle. Uh oh, 2:27 is out of character, although it still follows the thematic material, it sounds out of place. At times, I can't distinguish the solo violin (mainly when the full orchestra is playing). If you gave it a more rhythmic part, the listener could distinguish it. At 4:13 there is a little bit of a blues scale... which is out of character. Try to stay in character throughout an entire piece.
Thank you greatly for writing a good piece with coherency. So many people write without structure, and it just irritates me. I enjoyed this. I'm sure that whatever your teacher picks will be great!