Demand on ALL public transport to be free for under 21’s

Many people of a young age cannot afford to spend money on tubes and trains to get to school or collage etc.. everyday yet it’s the fastest means of getting there for them. If they are late they get into trouble and miss out on their education. Therefore I believe ALL transport (busses, underground services and train services coming in , around and out of london ) should be free too use for people up to the age of 21.