Too bad his mom is coming to town. Yes, the lady is an old school person, she says everything she thinks. And she can be a little offensive toward people she doesn't like. In other words, she's a bit of a racist. Despite the warning Dave gave him, Calvin accept the challenge.
Sure enough, Paula's stereotypical views of African Americans embarrasses Dave - "I didn't call him a monkey, but a grease monkey" ouch. At some point, he scolds her. Thank God, Marty and Malcolm are having a good time, which gives to the episode a funny tone.
In a surprising twist, Calvin tells Dave he needs to appreciate his mother while she's still around. Because he doesn't have all the chance anymore: "You know, she's the most important woman in your life".
I hope those people will stick around for one more season. It's not the best comedy in years, but I'm having fun watching it - CBS please renew the show.