The family have the old car two(?) episodes after Lois had won a new car in an endurance competition.
After Malcolm said to his parents "This is unbelievable, you actually expect me to be President?", he was holding a white towel in his right hand in the shot from behind, but after the next immediate shot, he wasn't holding any.
Abe, Stevie and Cedrick Hampton are sat at the table in Hal & Lois' kitchen. Abe picks up his teacup with his left hand. Change camera and we see him holding the cup in his right hand as he drinks.
Hal hoses Jamie down as Jamie is suspended on a chain. In one shot Jamie rotates to his left. Change camera, he rotates to his right.
Reese tries to make a mess that will take 30 days to clean up, but instead he could have just made a huge mess on the 29th day, so they would have to keep him the extra few days.
After the explosion of Reece's concoction, the grandma can clearly be seen with two legs whilst holding her artificial leg in her right hand. What's more, she's actually hopping on her left leg (the one that is supposed to be missing).
It is clear from the faces of Lois, Jamie, Piamma and others that the actors wore goggles while they were sprayed with the gunk.
When Lois opens the closet in the living room, it looks nice and clean inside and looks like a regular closet. But it's supposed they discover in "Therapy" that the closet was a second bathroom.