When Adam asks the truck driver to take him to his Dad's house, he says "Route 89" - when the piece of bark with his Dad's address on it clearly says 'Route 99'.
In the beginning Mrs. Harrison cuts Adams hair in the kitchen. the next day his hair has grown back, Adam then cuts his hair again. Later the Agents find his hair grown out in the trash, but the hair that Mrs. Harrison cuts is never seen again, it should have continued growing as well.