Strangers with Candy (2006)

Jerri Blank, a forty-seven-year-old ex-con, junky-whore, returns to her family after thirty-two years of being a runaway and a jailbird. When Jerri arrives at her childhood home, she discovers her disappearance caused her father to slip into a self-induced coma. Moved by guilt and the hope of waking her father from his eternal slumber, Jerri decides to turn her life around by picking it up exactly where she left off--as a high school freshman. She's committed to starting over, only this time she's going to do the wrong things the right way. In high school, a world that turns out to be much crueler and more cut-throat than anything she encountered in prison, Jerri tries to find her place--that special interest or pursuit that will erase thirty-two years of debauchery. She stumbles upon the school-sponsored Science Fair. Convinced that winning the fair will somehow resurrect her father, she signs up, expecting an easy stroll down the road to victory. Not surprisingly, her path is fraught with the many problems and temptations that plague all teenagers. But this former boozer, user, and loser struggles against all odds, determined to make her silly dream of redemption come true.