Tween Whitney Brown (Sammi Hanratty) is at the top of the food chain at her Philadelphia prep school—class president, a date for the formal with the newly arrived football star (“He’s still got that new guy smell”), and access to credit cards from her parents (Aidan Quinn and Brooke Shields). But when Dad loses his job and his money, the family must retreat to his childhood farmhouse in the nonspecified “country.” Up until now, Whitney has been a self-satisfied brat; her “greening” is the process of humility-through-humiliation that comes in adapting to flyover living, trying to make new friends, learning to ride the rogue Gypsy Vanner horse that trots around the house, and shoveling the stables under the guidance of the horse’s owner, who happens to be her estranged grandfather (Kris Kristofferson). This is intended as one of those kid’s comeuppance stories, in which a new maturity is won through contact with salt-of-the-earth types and honest labor but is done with an almost total lack of charm. Hanratty chatters constantly, and an inexplicable Dick Vermeil cameo will delight no one. The best that can be said is that in its shiny confidence in the entertainment value of blaring soundtrack cues (“It’s a perfect day for a girl’s getaway!”), pratfalls, and farting-horse comedy, Greening has a certain innocence.