Continuity mistake: When the kids are telling Beaver that he has to climb into the teacup, the kid with the heabands hair keeps changing. In one shot, it's hanging over the headband, and in the next the headband is in front over the hair, and it keeps going back and forth.
Continuity mistake: In the shots where Beaver and his dad are driving in their car, the car behind them keeps changing. It is really close, then really far away, and then really close again, faster than the car actually could.
Continuity mistake: When Larry and Beaver are eating cookies at a restaurant, Larry asks Beaver if he wants the cookies. Larry takes them, but when they leave, the cookies are back on the table.
Answer: His teacher wanted him to see a psychologist as he didn't seem to be hitting the mile markers other kids his age were. His parents imagined this when this was suggested as that used to be what seeing a psychologist meant back in the day. That if they found anything wrong, they would lock the person up in an asylum in a straight jacket. This was showing his parents' fear that he might end up there for seeing a psychologist.