First sample SAT with no studying - which scores are a good baseline?

I am a junior and took my first sample SAT test without studying just to see where I am. I got 650-660. Is that a good range for a baseline score? Can I increase my scores to the high 700s by taking a prep course?

Thanks!

Nothing but studying and taking the class will tell you. A class will likely help, or a solid self study plan with someone to help on questions you don’t understand.

Thanks!