I am currently a sophomore but I was hoping to apply to a school and get in for fall right at the end of my junior year.
Honestly, I do not think so in this COVID-19 environment and possibly next year as well. Although 99.99% of schools have made all submissions of standardized test scores options this cycle, quite a few have made them test-optional for next year as well and some even indefinitely.
Currently, there is more evidence that your UnWeighted GPA, course rigor (APs/IBs), Essays, and ECs are more important than your test scores and if you have high test scores you should submit them but they are just the "cherry on top" of the sundae, they are not what makes or breaks an admissions decision. With a low GPA, if you applied right now or next year, you wouldn't fare so well since you are competing with peers that have near-perfect GPAs, have taken 10 APs, have exemplary ECs like being editor of the newspaper, ASB President, or team captain of their varsity sport or have won Intel science awards, plus have evidence of intellectual vitality outside of the classroom ( college course, independent research, internships or published papers ).
Again, I don't know very much about where you are hoping to attend, your school rank, or what else you have accomplished, so I'm assuming you want to attend a competitive 4-year college.
My advice would be to use your full high school experience wisely and take as many challenging classes as possible like AP English (both or them) AP Physics, AP Calculus B/C, AP Chemistry, etc and get the highest possible grades and AP test scores as possible. Being able to do well on a 3.5-hour standardized test is no replacement for 1000s of hours of HS coursework, homework, projects, and tests. No one would ever place the same weight on a 1500 SAT test score as a 3.9 UWGPA with 10 AP classes under your belt.
If your goal is to get into the best college possible in order to secure the best education possible for your future, then there is no reason to apply to college in your junior year unless you are a certifiable genius who has already taken all the APs classes available and aced them and is simply bored of the lack of challenging classes available.
A high SAT can help make up for a low GPA, though from what I have seen most schools care more about your GPA than your test score. There are other factores that they will take into consideration, such as why is your GPA lower? If your grades went down because of covid they are more likely to be understanding than if your grades have been low throughout high school.
Is there a specific program you want to enter that allows you to start college early?
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