The best way to meet new people at school is to join extra-curricular activities. Find something that interests you or that is a hobby, and join a club, activity or group related to that.
Also, don’t be afraid to talk to people you want to get to know. It may be awkward at first, but it is by far the best way to meet people. School also gives you plenty of opportunities for conversation starters.
Here are a few easy ones:
-The homework you had in class the previous night
-The food in the lunchroom
-The school football team