One example is the Sestina, which is comprised of six stanzas of six lines each, and concludes with a three line envoi. The envoi, which is the seventh "block" of text, doesn't count as a stanza.
Check this out: http://writing.upenn.edu/~afilreis/88/stevens-13ways.htmlBasically, each stanza describes a "theme." For example: If you are talking about candy, one stanza might be about how people...