I don't think you can do that. There are only a few ways to number the weeks
and there's not one that covers your example.

"Wsagazoid" wrote in message
...
I want to keep track of what week it is in each of the four education
terms.
Each term lasts 12 weeks with a winter break of 4 weeks. I also like to
be
able to number the weeks in thirteen groups numbered 1-4 for a different
calendar application. Such as: Period 1 Week 1 or Period 11 Week 3.

Any suggestions?