*Q: I am a high school junior, and recently failed 4 out of 7 classes I am taking. Last year, as a sophomore, I also failed English. But I got a 1270 on the PSAT, so I'm in the 90th percentile there. I wonder, conceivably, if I turn my act around, will I have a chance to get into a state school with around an 80 percent acceptance rate?
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A: Short answer: I don't know!

Longer answer: Your statement raises many questions. There are, as I see it, three major issues:

Are your low grades the result of a slacker attitude? Your phrase "if I turn my act around" leads me to believe so, but I cannot be sure.
Have you ruled out any learning or processing issues? There is a reason for your getting low grades. And your low grades occur during both sophomore and junior years. This will not only wave a red flag when you apply, but the flag will be flapping furiously.
Some state universities are getting very competitive, and many are already there. Because private colleges cost so much now, there are more applicants trying to gain admission to lower-cost schools, and you will be competing with them. Students with better, and more consistently better, academic records will be the first ones chosen.
You still have options, so do not despair.

First, are you sure you wish to go to college at this point? If you are not academically oriented, you may wish to take a year off after high school graduation and work. During that year you can think about applying.
Or you might be a "late bloomer" and just now, in the middle of your junior year, you have decided to get serious.
My advice: Do the best you can in all of your subjects. If, at the end of this year, your grades are still disappointing then you need to speak immediately with your guidance counselor about having your work evaluated. To repeat: There is a reason for failing grades.

On the other hand if, at the end of this year, you do indeed turn your act around and get decent grades, then you are on the right path.

This in itself does not guarantee admission to the school of your choice.

Admissions readers look at the entire high school record, and they will see a pattern that may be repeated in college. Students with good grades generally continue to get good grades, after experiencing the general dip in the first college year as they adjust. Students with weak grades tend to keep getting weak grades. But students whose grades go up and down are more unpredictable. The grade report—the transcript—tends to be a better overall predictor of college performance than test scores. The test scores, however, show that you are capable of doing well.

Towards the end of this semester, make an appointment with your college counselor. You may indeed find acceptance at a smaller branch of your state college. Or you may wish to start at a community college. Either way, if you do well, you can apply to transfer to a larger four-year school after two years of study.

The key will be your track record. You will need to prove that you are capable of academic success before you can find your true academic home.