Though the movie weaves many side stories in and out of it, the through-line of The Peanuts Movie is in whether or not Charlie Brown will strike up enough nerve to talk and get to know the new girl in the school he develops an instant crush on (he's dubbed her the Little Red-Headed Girl -- she's traditionally never actually seen in prior works, but we finally get a glimpse of her here).  Taking place over the course of a school year, Charlie Brown seizes upon several opportunities to put himself on her radar (a dance competition, a talent show, acing a test, and a book report on "War and Peace"), hoping that being seen as a 'winner' will give him the leverage necessary to overcome the instances when he feels like a loser with a perpetual streak of bad luck.  In between this are several interludes, many showcasing some Snoopy solo daydream adventures where he "dogfights" the dreaded Red Baron to fight for the love of a French poodle named Fifi, high in the clouds, which is where the film's choice to render 3D animation is put to good use, even if repeated visits are a bit of overkill.