Visible crew/equipment: After Bobby tells Alice that he can't pass Jan the potato chips because he's "not here", when Greg walks in and Bobby tells Alice that Greg's "not here either" we can see the tape mark on the floor behind Jan.
Continuity mistake: While the kids are practising the potato sack race as Jan watches from the sidelines, when Marcia steps into her sack and hops away there's a large color image on the front of the sack, but when she reaches Peter, then turns and heads back the image has vanished - it's not on either side, then it reappears when she's back with Bobby. Additionally, when Cindy hops in the sack that Greg was in, the sack is ripped at the bottom and Cindy's feet are on the grass, but when Cindy reaches Peter the bottom of her sack is perfectly intact.
Answer: I think I remember that episode - but, more importantly, my mother always told me (and my siblings) to stop jumping/ stomping, running in the kitchen, and opening the oven door when a cake was baking... because these could make the cake fall. I believed my mother... and I, as a child, also caused a few "fallen cakes" because I didn't quite always listen (right away, anyway). I'm sure Alice's fallen cake episode was exaggerated, but cakes really CAN fall from stomps and opening the oven door too soon. Usually, it has something to do with the baking powder and how the air bubbles change during the baking process. Doing something that might cause the oven and cake inside to move/shake can suddenly change the air bubbles inside the cake and cause a collapse. I don't know all factors that have to occur for a cake to fall (collapse in the middle), but I've seen fallen cakes during my adulthood and... well... caused at least a few myself. Regarding Alice's cake falling each time one of the Brady kids stomped upstairs, I'm not sure if a series of falls could occur. IF it is possible, I think there would have to be way too much baking powder in the batter or some other inaccurate combination of ingredients that alter the chemical process during baking.
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