A scooter device propelled by side to side movement of a user that includes a frame structure through which at least a front wheel is coupled to two direction biased rear wheels. The frame structure may have a foot placement platform that extends laterally between the two rear wheels. The platform may extend over half of the distance between the rear wheels and/or be substantially continuous for that distance. Various platform embodiments and frame structures, including rigid and flexible, are disclosed, among other aspects.