How to raise my grade for 7th grade?

Hello, i'm in 7th grade. My first quarter average is 91. And i want to go to Townsend Harris, but i have to get 98 for every subject, because i got 91 on the first quarter average. I don't know how to raise my final grade. You see, in high schools, they look at your final average. So, what do i do, if it's lower? i can't do community service. So can i do something like volunteering in church??? My school is IS 25Q, please help me and answer your best! thank you so much