Continuity mistake: From the outside of the house, you can see the staircase and door are to the far left of the house. But from inside the house, you have a fireplace and the staircase to the right of the door. So you know it's not the same house they use in the show.
Continuity mistake: Whenever the characters in this sitcom fall through the roof, they end up on the living room floor. The house is a very conventional design with a second floor and an attic, so they should end up in the attic or on the second floor.
Continuity mistake: The Winslows' front porch as seen from inside their house features a lattice wall with vines and furniture. However, establishing shots of the house show no such features.
Answer: It was just cancelled. Read more here: http://www.kellie.de/end.htm.
Myridon