That being said, John C. Reilly holds down each and every scene he's in, only faltering when the script lets him down. He plays Mr. Fitzgerald, the principal (or maybe assistant principal) who takes the disillusioned Terri (Jacob Wysocki) under his wing. Reilly plays glib but sincere, spinning off of his usual persona (most drawn out as Dr. Steve Brule on "Tim and Eric Awesome Show, Great Job!") into more complex areas, places I haven't seen him go in a long time--if ever. It's the best performance of his career by far, giving Jacobs exactly what he needs, transcending the minor problems written into his role.
Terri is considered a "good-hearted kid," that is, he has an extremely strong moral center. Stuff gets in the way of that sometimes, but ultimately, he knows what's right and wrong. The problem is, he's been having a hard time keeping up with the bare minimum requirements of school, always showing up late to every class. This is not helped by the fact that he needs to take care of his unstable Uncle James (Creed Bratton, most famously known for "The Office," though he's not exceptional here), not to mention his obesity (which gets him picked on and gets in the way of his getting with his romantic interest, namely Heather, played by Olivia Croicchia). A number of things happen, though, that point to leading him from glumness. His counseling with Mr. Fitzgerald is the most prominent catalyst, even though that involves some tremors. He also gets closer to Heather once he lifts some of the burden off of her that resulted from a pariah-making PDA. But catharsis doesn't come so simply in the end, emotionally and otherwise, especially because of two other characters: Mr. Fitzgerald's dying secretary Ms. Hamish (Mary Anne McGarry, who gives more than what seemed possible in the confines of her role's original one-joke routine) and consistently problematic Chad (Bridger Zadina), who seems to be the product of some sort of emotional neglect.
I appreciated the film's comedic aspects (Wysocki and Reilly are strong in this field), as well as the awareness it has of its characters. However, I found certain bits of the story nebulous, especially towards the end. It's nice how Jacobs and Dewitt don't feel the need to spell every little thing out, but I would have been happier if the resolution had felt slightly more assured. "Terri" has definite plusses, but lacks in depth where it could have been well-shaded, and thus probably will not age terribly well. B