Pants on Fire (2014) on Netflix

Plot summary

Jack Parker is popular at school and has a shot at a scholarship that would make him batboy for the Boston Red Sox. He has also gotten through life by lying, including the invented student he claims to tutor so he can skip chores. When he gives a speech, that student, Mikey, turns up in the room, and Jack cannot get an answer about where he came from. From there his other lies arrive one after another: two angry lumberjacks, and Lisa, a jealous girlfriend from Arizona who ruins his attempts to get close to Jennifer, the girl he likes. Jack watches Mikey and Jennifer become friends and, jealous, tries to separate them.