Hi Excel-lent People,
I am trying to average assignment scores in a gradebook. Assignment
scores are entered into cols starting with AO. On row 10 are the max
points possible for assignments (for instance, AO10 may be 20 for 20
points poss). Students begin on row 13, and, if students do not need
to do an assignment, I will leave their cell blank for that
assignment. I cannot solve how to write a formula that will exclude
null cells when max values are still present in row 10. Here's what I
have:

Formula in O13 to compute Assign. Points Possible:
=SUMIF(AO13:AO13,"0",AO$10:AO$10)

Formula in P13 to compute Assign. Points Earned:
=SUMIF(AO13:AO13,"0",AO$13:AO$13)

Formula in Q13 to compute Assign. % Earned:
=AVERAGE(IF(($AO13:AO13<"")*($AO$10:AO$10<0),$AO 13:AO13/$AO$10:AO
$10))*100

**Here's the key--the student in row 13 may get a 0 on an assignment--
AO13 would = 0 and then Q13 would then = 0.00, which is the same
result as if the student didn't have to do the assignment. Other
formulas will use this value of "0"

If AO13 is left blank, how can this formula produce the desired
result?

I would like to simply figure each assignment percent for each
student, then average all of the assignments for a student during a
quarter.

Thanks a bunch!!!