Scooters

Does anyone know the requirements for riding these small scooters around town? Does the requirements diminish because the scooters are smaller. I notice there are no plates on the bikes. Do they need a driver's license? The reason I ask id I've seen more and more of these vehicles weaving in and out of traffic. They've gone as far as riding between two moving cars on a two way street. I've also seen them drive across lawns along black rock turnpike.