My dept basically just uses an Excel sheet to create a table. Room names
along the top, times along the side, block in the classes, one table for
each day of the week. (Or actually, I think my department does weekdays
along the top, and a separate table for each room).
You can even color-code teachers, or subjects, or whatever you need to be
alerted to.
Software to do this sounds expensive--the sort of balancing necessary seems
to require a pretty human intelligence, that will be very specific to your
school.
A template sounds useless, as the start/end times and classroom names will
also be specific to your school, and you'll have to customize it so much it
will be easier just to write your own. However, check here:
http://office.microsoft.com/en-us/templates/default.aspx
For simple tables like that, even a total newbie in Excel should be fine.
Just open it up and start playing around with documenting a schedule, save
the final version. You can save it as a template. If you need help with
Excel, though, look for an Excel newsgroup to ask questions.