The answer to your question depends on several factors. First, do you have a safe route to school? Bike paths away from traffic are clearly the best. Second, how much time do you have for your ride? Third, is your bike in good condition to make the ride? Fourth, are you in good enough condition to start these rides? Remember, with repeated rides you will get more fit, and your ride speed will increase while your ride time decreases. And lastly, is there a safe place to lock your bike up at school? Anytime you can ride a bike instead of drive a car you are helping the environment as well as improving your overall health.