227 ends its five year run on NBC with Brenda graduating from high school. I think this episode was more intended to be a season finale but became a series finale with the declining ratings of this season for the series. This episode centered around Mary having to go to the hospital and trying to sneak out on several occasions to attend Brenda's graduation. Mary finally realizes that she needs to have her operation and misses the graduation. Brenda and the entire cast come in to see Mary at the end of the episode with her cap and gown on.
Some people would argue that this was probably a forced ending episode, others would say this was more intended to be season finale and some would say that this was a good ending point with the graduation.
I'm glad to see that some closure was brought to this show after Gibbs' other series The Jeffersons was abruptly cancelled in May 1985