It's another Japanese silent short with elements of comedy. It didn't work for me, partly because of cultural differences.
The title means "The Pure Heart: Moral Fables for Young People". Boys and girls! You must be pure like Mount Fuji and have noble hearts.
It starts with a sick mother sending her daughter to the doctor to buy some medicine before it gets dark. The daughter's running along when she trips, drops the money and has a laughably brief search for the missing coin. She immediately gives up and goes home, crying unconvincingly. There's also some questionable visual storytelling. In the shot where the daughter trips, she's almost reached a bridge over a small river. There's a cutaway of the coin landing by the side of the road, then in the next shot, the bridge is behind the camera... but the daughter never looks in our direction. She doesn't even glance towards the bridge or in the water. It's enough to look like a continuity error, although it's not. (The same milestone is beside her in both shots.)
Immediate diagnosis: a director who doesn't give a toss. (We might cut him some slack since it's 1925, but let's not.)
Anyway, the next day she returns to look again. (Why didn't you look harder at the time, eh?) A teacher (Sakai) sees her, takes pity on her and gives her some money. He has a worry, though. He thinks he saw one of his pupils pick up something from the road. Was it the missing money? To judge by Sakai's reaction, this would seem as serious as mugging the girl and stealing the coin by force.
"The teacher prayed Masaichi wasn't to blame. But if he were, he wanted him to repent by himself."
What? It's the following day. In the road. You'll fall about laughing... but, actually, that's very Japanese. I remember a story from someone at my bridge club. On a business trip to Japan, he dropped his wallet full of money at a busy railway station. On realising this, he was distraught, but his translator assured him that this wasn't a problem. It's Japan. No one would have taken it. My friend returned to the station a good hour later and, sure enough, the wallet was still there on the ground, completely untouched. All his money was inside. That would never happen in the West.
That story makes sense of this film. Let's return to the plot. Sakai is addressing his 6th grade class (roughly 11 years old) of schoolboys, all of whom have shaved heads. They're terrifying. They're like a skinhead gang. Sakai tells them a story with a moral. "Lastly, let's talk about something interesting. Honesty is more important than anything else. You must all be honest. Once upon a time there was..."
...and suddenly we're watching a story-within-a-story: "The Honest Porter of the River Abe". This is a samurai-era historical and a failed comedy. Someone drops a lot of money by the river bank, so the porter runs after him to return it. The non-customer (who'd gibbed at the price of a boat) thinks the porter wants to rob him, so he runs away. This leads to unfunny slapstick as the non-customer tries unconvincingly to hide in some baskets and a cupboard. Two ladies participate in this... but it turns out that they're the porter's wife and daughter. Dad runs up.
PORTER: "A young man came this way. He must still be here. Where did you hide him?"
WIFE: "There's nobody like that here."
PORTER: "I saw him dive in here."
DAUGHTER: "Father, please don't consider doing anything bad. No matter how poor you are you mustn't do bad deeds. Please stop."
The obvious thing to do here would be to explain the situation. Our hero doesn't do this, because the film needs him to perpetuate the comedic misunderstanding.
PORTER: "There's a reason why I must catch that young man. Let go of me!"
Now, we're told that this is a poor family struggling to repay a 5 ryo debt. (The dropped money is 300 ryo, so our hero is being noble about more money than he'd probably make in a year.) The creditor appears.
CREDITOR: "I cannot wait today. Repay me the money now."
PORTER: "Please, for pity's sake, wait a little."
CREDITOR: "If you cannot pay in money, I'll have your daughter as per the agreement."
Note the last three words: "as per the agreement". WHAT THE HELL? These people took a loan with their (underage) daughter as collateral? No one sees anything unusual in this, including the daughter herself. Okay, yes, they're poor, but but that's not a universal explain-all.
Fortunately, though, the chap who dropped that money is willing to help. "The youngster thought it a pity for this to happen over 5 ryo." Well, yes. A pity. That's one way of describing it, I suppose.
The story-within-a-story ends and we return to the present day. (Albeit still almost 100 years ago for you and me.) Sakai's still treating a boy picking up an abandoned coin in the road as the equivalent of grand theft and larceny. "After hearing this story, do any of you have anything in your heart you're ashamed of?"
There's a happy ending, in which it turns out that Masaichi isn't a scoundrel. Sakai apologises. "You've such a pure heart. If all did like you, there would be fewer road mishaps. I am so sorry I suspected you even just a little."
This film is both bonkers (to a Western audience today) and incompetent (even compared with other silent-era films). It's a silent-era comedy, e.g. that bloke being carried on a ladder and then tipped into a river. It is, though, so badly made that all the comedy is unfunny and you might only realise an hour later that it was even attempting that genre in the first place. It will, though, repeatedly boggle your mind, which one rarely gets from much better films.