Quarrelling Tess, a widowed psychiatrist getting remarried on Saturday, and resentful 15 year-old daughter Anna, a garage rocker with problems at school, are magicked into each other's bodies for a fraught Friday of unfamiliar challenges, romantic complications.
Besides the obligatory wiseacre kid brother, no teen flick is complete these days without the ingenue performing a music promo.
So this body swap fairy tale climaxes in a band audition at Hollywood's House Of Blues. Happily, Jamie Lee Curtis gurning through a guitar solo (she is Lady Spinal Tap, after all) while her floundering 'mother' mimes on stage is amusing - as is this amiable wheeze in general. Adapted from Mary Rodgers' juvenile classic of comedic life lessons, it's a sensible update of the 1976 Jodie Foster version, in which a girl not knowing how to operate a washing machine was as wacky as it got.
Now Mom, in her daughter's guise, tackles school bullying and young lurve - taking an excruciating turn when the boy is drawn to the older woman - while the teen-as-mother has fun with Mom's psychiatric patients, fending off her amorous fiance and endangering the wedding.
Cute and innocently funny, with engaging turns from a beautifully silly Curtis, and Lindsay Lohan as a 21st century high school heroine.