Will i get into St. Agnes Academy in Houston, Texas?

I have to say my math grade was bad in 7th grade. My English was in the 80s. My other subjects were in the 90s and 100s. I am now going to 8th grade and will try my very best. if i do really good in 8th grade will i have a chance of getting into St. Agnes? ONce again my 7th grade grades were bad. Does St.Agnes concentrate on 7th or 8th grade the most? plz no harsh comments. i was really stupid in 7th grade ,but now i wish to get 100s in 8th grade. Will i still be able to make it in St. Agnes even though my 7th grade grades were bad? Will i at least get put on the waiting list? Ty for your answer