I just figured this out, but I dont know if it applies to all universities so you should call your records office to figure it out.
basically you have your credit hours (ex. Bio 3 credits, chem 4 credits, etc) and your QP hours (it could be called something else at your school).
The QP hours are a certain total value but decrease with the grade you earn. this is the table:
A: 4 QP
AB: 3.5
B: 3
BC: 2.5
C: 2
CD: 1.5
D: 1
Basically you find the grade you got in the above chart and multiply the value by the number of credits that class was. For example lets say you got a BC in a 3 credit Bio class. you find the BC grade in the above chart (2.5) and multiply it by 3 (the credit value of the class) and get 7.5 QP. After doing this with all your classes, you add all the QP points and all the credits you have separetly. then you divide the values out:
Total Qp
--------
Total sci credit
and the value you get is the science gpa.
im still trying to figure out if math and computer science count in the gpa.
i hope that helps and wasnt too confusing.
good luck!