I took Algebra 1 Honors and Geometry A in 8th grade but had a 87% in the first semester and a 90% in the second semester. I want to have an A, so I am planning to retake the math course over the summer.
How do colleges look at the course
you need to ask your high school - at our high school anything taken before the start of 9th grade is no credit/no grades on transcript etc - basically you just start at a higher level but would still need 4 years of math taken during actual high school year. Also if not taking directly from the school you need to confirm with the school that they will accept/count the grade/credit. If it is simply an 8th grade class colleges will never see it.
Find out from your school (not on here) how they use the grades and if both sets show up on your transcript sent to colleges. If a college sees that you retook a class for an 87 and 90 they may not think highly of that (grade grubber type thing) and if they see you retook it without seeing the original grades they may think bad grades - you were not ready for it in 8th grade. They may also say not the best grades good choice to retake for a higher level of understanding.
You may look bad from it. Colleges will wonder what got into you that you retook a class where you got a B+ and an A- in.
Do something worthwhile with your summer. Look at where needs are right now, and go help.