What do you think of this excerpt?

Well for your age range I'd say this is very well written. Just always be careful to never mispell the names of your characters. At the end it mentions Seph when I'm pretty sure you speak of Steph. Sometimes authors chose to use similiar names so that might confuse a reader to think it was a different speaker. Make sure when using speech to have it clearly defined who is speaking and to who. Your spelling might need a slight bit of work. Don't limit your vocuabulary! Use a thesaurus :) The sentence structure seems to be well done. I know this is just an excerpt so make sure to clearly define the characters later on since they need it a little. Other than that, fantastic work. I hope you don't think I was harsh, I'm simply used to grading English :P