Absolutely. Everyone in high school is usually lacking in absolute strength.
The way a powerlifter benches is more efficient and safer. It will save you from unecessary shoulder rotation and get you in a tight setup where injury is less likely to occur.
Obviously, you don't have to get wider than the rack when you squat, but low bar squats are great for posterior chain emphasis, important for athletic performance.
As for the deadlift (and this goes for squatting too), it is important to learn proper and safe techniques period. There is not as much of a "PLing" dead though, especially if you're pulling conventionally.
Read the articles by Dave Tate, Robertson, and Cressey. Also check out WSSB by DeFranco once you have read about methodology and exercise setups.
These articles have helped me immensely to become a more efficient and stronger lifter. Best of luck to you.