Was the cast aware that the show had been cancled when the did the last season?

The last episode seems kind of just blah. Nothing was wraped up like in the waltons.

Did Beaver have a look back episode for their last one?

They probably knew they were in trouble when the ratings tanked in the last season. Somebody else can probably recall these details better than I.

And, yes the last episode was nothing special. To say something positive about that season, it has one of my favorite episodes, "The Enthusiast." Beverly Garland had episodes that really showcased her talents in this season; another of those is "Bad Day for Barbara."

Yes, Beaver had a clip show which was a final episode. Connelly and Mosher ended that show at its logical time, when both boys were going on to new points in the education.

I believe I read that they were not aware they were going to be cancelled. Probably for most shows at that time anyway there would have not been a final episode just a regular episode. Seems like the special final episodes started being more common after "The Mary Tyler Moore Show" ended.