Live in the moment
There are good and bad things about high school (as with everything else) but you have to learn to embrace these moments. Whether it's staying up till 2am cramming for an exam or finishing the essay you procrastinated on all week to turning 16 or hanging out after school, every moment counts. By living in the moment you'll be able to enjoy everything which makes those fun moments that much more fun.
Make friends
This might be a pretty obvious one but having a social life in high school is just as important as everything else. Sometimes things may get stressful or you'll go through tough times and having a solid friend group will greatly help you speak about your feelings and get through these times. Some things you just can't do alone which is what your friends (and family) are for.
Get involved!
I can't stress this enough! Get involved with clubs or volunteering opportunities!! Not only will you get to meet and speak with some amazing students they're great for college applications and your resume even! Extra circulars are also a great way to spend your time if you're just going to and from school. You can even pick up a new hobbie this way!
You walked in as children, but before you know it, you'll be walking out of those doors as adults. Remember to make every moment count.