Watch Pony Girls for Free: How to Stream the Movie Online at 123Movies. . About girls who ride with horses and grow bigger. The film follows three years of age 9 to 19 year old girls who perform ponies and horses at the Poni-Haha Riding School in Hakunila, Vantaa. At the beginning of the story, 12-year-old Laura and his friend Nekku and Heli are in the middle.