Okay, I just watched this movie.
I felt that the movie itself held a lot of promise, and while it could have been better, it lived up to my expectations. The portrayals of the main characters were very well done, borrowing from the standard tropes of the unpopular kids without going overboard into ham territory. In particular, the chemistry between the two main characters of David (Jonny Weston) and Jessie (Sofia Black-D'Elia) was very palpable, even from their first meeting.
Now, the biggest plot hole of this movie is the initial catalyst that caused the main character to find his father's plans for the time machine to begin with. That plot hole is the idea of him being $20,000 short to go to MIT. MIT practices a system where if you get admitted to MIT, MIT will make sure that you will go, even if you cannot afford to. They admit you based on your merit and what you can bring to the school, not on whether or not you can pay the bills. Basically, if you get in, they want you focused on your studies, not your tuition and fees.
Tossing that little nugget aside, the rest of the movie is actually very tightly written and decently researched.