My twins transferred from a private school to a public school at the beginning of their sophomore year.
Their private school GPA calculation was more rigorous than the public school. For example, a 90 or above gets a 4.0 in their public whereas a 90 in their private school gets a 3.5.
Both girls had 3.25 cumulative unweighted GPA’s in private school their freshman year. They have just finished their first semester in public school. They both took 8 classes - 4 honors and one AP, and the other 3 classes on grade level.
Both girls received straight A’s their first semester in those classes.
Therefore, they had 3.25 GPA unweighted their freshman year (8 credits) and 4.0 GPA unweighted their first semester sophomore year (4 credits).
Today we received their state Achievement Record and somehow the school has calculated a 2.81 cumulative unweighted GPA.
I wasn’t a math major but that’s obviously wrong.
I intend to follow up of course. Specifically, I want to know the district policy as to re-calculating their first year of private school to their public school criteria (a=4 etc.). If so their GPA would have been higher obviously for 9th.
This makes even more obvious the discrepancy of the improving grades and straight A’s actually reducing your GPA. 
So the question is - what the heck? We compared side by that each semester grade was input correctly - both the transferred grades and current school grades. So the numbers are correct. The total number of credits is correct.
How would this have happened? Is it common? I’m surprised we have to do our own spreadsheets and double check this.
Has anyone else experienced a gpa error?
THANKS!!