I am in 9th grade and have been curious about this question for a while.
I’m pretty sure they can only see what is on your transcript. If you hit a low grade in a class but later retook it and did better, I think they can only see the replacement grade.
Colleges can only see your final grade in a class and nothing else. For example your current grade in Biology is 89 but by the end of the semester your final grade on your report card is a 96. The only grade that will be there for Biology will be a 96 and that's all the colleges will see.
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