The boys, somewhat manipulated (guided?) by Ward's advice, decide to buy stock in a local utility. The name of the company changes considerably as the story progresses. First, at the breakfast table, Ward calls it "Mayfield Power and Electric". Minutes later, as they meet Eddie on the front porch to walk to school, Wally refers to it as "Mayfield Power and Light". Then, at dinner one night, June refers to it as "Mayfield Electric and Power". Solid, dependable stock, perhaps, but a highly variable name in the words of these actors.
In the epilogue, Beaver mentions practicing what the Bible teaches about "helping yourself" by keeping a bedside lamp on at bedtime to generate income for the power company in which the family owns stock. Although the boys may have heard it in Sunday school, the old maxim, "The Lord helps those who help themselves" is derived from Aesop's Fables, not the Bible.