Learning you use, not learning you read.
Working models you drive yourself, where the figures recompute as you move them, and where every answer explains itself either way. Each one runs in the browser. Nothing to install, no account, and nothing leaves your device.
One published. Each is self-contained: a subject taken end to end, built to be used rather than skimmed, and free to open.
Forty six rooms across four floors, covering how companies are owned and run, how finance actually works, how selling and marketing work, and how operations turn inputs into something worth more than they cost. Each room is a printed chapter with working models you drive, then a lock of five to ten questions that has to be picked before the next door opens.
Forty six working models. Break-even, the cash gap, the bottleneck that makes improving four stations pointless, the channel with cheaper clicks and more expensive customers, and the call centre target that improves the number on the wall while tripling the cost per problem solved.
More will be added here as they are finished. Each will follow the same rule: something you operate rather than something you read, small enough to finish, and honest about what it does not cover.
They are not courses. There is no enrolment, no cohort, no certificate that anybody else recognises, and nothing is graded by a person. They are working models with the reasoning attached, built because explaining a mechanism is faster than describing it.
They are free and they carry no sales material. If the work here is useful and you want the same thinking applied to your own situation, that is what Services and Start Here are for.