Beaver has a substitute teacher for a couple of days, a "Mr. Willit, played by Wendell Holmes. "Mr. Willit" is good at teaching history with World War II stories. He asks the kids if they have anything to add. Several get up and tell how their fathers were heroes, the worst being "Judy Hensler," of course, the most obnoxious kid in the school, and the biggest apple-polisher. (She and Eddie Haskell would have made an interesting couple, had they been the same age. That reminds me: Eddie hasn't been in an episode here in months.)
Anyway, outside of class Judy starts picking on Beaver so Beaver responds as he usually does, meaning his lies his butt off, telling what a big war hero his dad was and that he has a trunk full of medals, machine guns, hand grenades, etc., at home. The teacher overhears the argument and sticks up for Beaver (Judy was yelling at Beaver, calling him a liar - the only thing she ever got right.) and tells our boy to bring some of that stuff into school for a show- and-tell-type presentation.
At home, Beaver and Wally go out to the garage and dig into that old war chest of their dad's. The first thing they see are pictures of women. "Wow, I never knew Dad knew so many women," said Beaver. "Those aren't women; those are pictures of Mom," answers Wally. (Actually they were, too - pictures from the 1940s of Barbara Billingsley. A younger-looking and long haired Billingsley was interesting to see.).
The boys then discover other souvenirs from the war, except they turn out to be measuring devices. It seems Ward did surveying work for the Seabees. Beaver is disappointed. "I thought he did more than just measure dirt," he says to Wally.
To make matters worse, Mr. Willit calls up Beaver that night to remind him to bring in the war souvenirs. He adds, "nothing dangerous, however." Holmes was interesting to watch as the substitute teacher and he does Beaver a big favor at the end.
Beaver gets Wally to write a fake letter, pretending Ward is writing June during the war telling him what a hero he is and what he's doing. That part was hilarious.
How Beaver gets out of another jam, or the lesson to be learned, is the rest of the show. One good thing: Beaver finally learns something about embellishing the truth, and how it isn't a good thing to do.