how to make a paper boat

So I spent my day making paper boats, to float in the bath. Hours of high quality toddler entertainment, fiddling with the half-remembered folding technique that makes a reasonably watertight gondola. Then experimenting with different papers for optimum non-sogginess (hot tip: pizza flyers, the stiff shiny ones from dodgy looking outlets on industrial estates. And glossy magazine covers. Those featuring Jennifer Aniston seem particularly water repellent).
There won't be many more relaxed days for a while. The election's no doubt going to be called next Tuesday, so bang goes the next month (I have, obviously, broken my promise to myself to stay out of it. But am MOSTLY staying out of it. Ahem).
But the paper boats were a useful reminder of two things. One, obviously, that if you're two the best things in life often really are free.
But secondly, how much harder parenting would be without the interweb. I couldn't remember how to make paper boats, so obviously I googled it. (What DID parents do pre-Net? Talk to each other? Hand wisdom down the generations? Surely not).
There are millions of variations - I picked this video at random. But almost all those I looked at were not trying to flog anything (what paper boat-associated merchandise is htere? old paper?), advertise anything, puff anybody's paper boat-related book, sucker you into being their friend, or get your bank details.
People just go to the bother of filming themselves making paper boats and posting it online for the sheer joy of - what? Maybe some origami-based sexual fetish, but more likely just because there is a compulsive human need - and one particularly strong among parents - to share stuff that might make others happy, and to teach what you know. For all the ugliness and criminality online, there is sheer altruism too.
Also please note: say what you like about online news, but you can't make a boat out of it, can you? I rest my case for old-fashioned newspapers.