You manage your own time. You need money for entertainment and special purchases. You need money for everything, including basics. Textbooks are free. The school loans them to you.
Textbooks are very expensive.
You buy them and may be able to sell some of them back for a percentage of what you paid. Parents and teachers provide a lot of guidance. You will be faced with many new moral and ethical decisions. You must make these decisions yourself. Parents and teachers correct you when you break a rule or do something they do not approve of.