Complex sentence: St. Joseph's football team has won 18 state championships since 1983, including 11 state championships in 13 years through 2011 and have won three consecutive state championships as of December 2011.
Split into simpler sentences: St. Joseph's Football team has won 18 state championships since 1983. They have won 11 state championships out of the last 13 years, and have won 3 consecutive state championships as of December 2011.