Help with Gradesheet calculator

[teomi]

Hi all,

I created a really basic grade calculator for our College. (attached here).
Currently it is really simple. It accept grades for 4 projects (PR1-4) in 4 categories, and a final test.

The final grade is basically a percentage average between the 4 projects and the test as follows:

PR1=10%
PR2=10%
PR3=10%
PR4=30%

Test=40%

Here is my challenge:

Sometimes our courses have no test, and sometimes we have 3 projects and not 4.
I want to implement a condition that if a grade cell is left black (or at zero) it will not be used for the total final grade calculation.

Obviously if there are only 3 projects or no test the percentages will change.
Something like that:

PR1=15%
PR2=15%
PR3=30%

TEST=40%

or if no test:

PR1=15%
PR2=15%
PR3=30%
PR4=40%


Thanks in advance for any help!!

Eitan

[yay_excel]

How about this? (See attached).

The user must manually enter the weighting for each of the PR1-4 and TEST. It is currently at your default 10-10-10-30-40. If one does not count, enter 0 for it.

[MarvinP]

Hi Eitan,

I used to teach high school math and have given thousands of grades. My sugestion is to never average percentages, period!

See http://wiki.answers.com/Q/Can_you_average_percentages

To be a more accurate grader I used to convert each test score to a Student T score, where 50 was the average and 60 was a standard deviation above average. See http://pareonline.net/getvn.asp?v=4&n=8

It is legal and mathematically correct to average standardized test scores.

I was always in trouble with the principal (the x basketball coach and PE major) as he could never figure out how I could average Z scores instead of percents. I knew I was the best grader in the district and realized I couldn't teach the PE majors why averaging percentages was just WRONG!

[teomi]

Thanks all for the suggestions! They are much appreciated.

Eitan

[MarvinP]

Hi Eitan,

Here is more reading about giving acurate grades.

http://www.ericdigests.org/2003-4/sc...ilization.html