Generally public schools hand out high school directories to current 7th graders in May/June. You should also be able to get a copy at a family welcome center. I would call first, to make sure they have copies on hand:
I also suggest you download last year’s high school directory:
The DOE generally takes down the previous year’s directory when the updated version is in full circulation. I still find it easier to skim through this—even a pdf is easier than trying to find at the MySchools site. TIP: print out pages of schools you’re interested in and then update any info that has changed since last year.