Lois: Okay, now listen up. I'm going to give you each $10 to buy me something.
Malcolm: [to camera] We've never done this before. Usually, on a birthday, we just make her stuff.
[flashback to Lois holding a potato with a coin stuck in it and "Happy Birthday" written on one side, and "I love you" on the other:]
Lois: Honey it's... nice.
Reese: It's a potato bank. I made it.