iCal text adjustments

My father needs help with Mac's built-in calendar, iCal. The application works well enough, although the text is too small for him to read. I have searched around for a way to enlarge the letters in this application, but so far can't seem to find how to do this. Any suggestions?

If the size of the text cannot be changed, any suggestions for a similar Mac-based calendar program with larger letters?

Thanks, Keefe

thank you

Thank you for the reply. Idid do a quick search before asking, but somehow I missed this thread.
Best, Keefe