I see a lot of questions about transcripts, so I thought I'd put this out here. I decided to register with The Farm School as our umbrella program in TN for the "high school" years, in part so that I could do exactly this, and generate a transcript as we went. At the end, if we want, The Farm will create a diploma for us. The transcript is generated via a simple online program - I'm sure there are tons of the darned things, but the one they use is homeschoolreporting.com in case you're looking for one. One of the handy features is that when you go to type in a "class" it gives you a long list of suggested high school classes so you can use something that sounds nice and normal. You can also assign grades and credits if you want.
So this is what the transcript looks like for Morgan's "freshman year of high school":
Computing - graphic design
Ancient history//World Geography
But we're unschoolers, right? So how the heck did she manage that? Do we do online classes or something? Nope. Not a bit of it. I keep an eye on the sorts of things she's doing - what she's reading, writing about, drawing, watching, playing - and I take notes on that when I think about it. Then around the turn of the "semester" I look through my notes and see what would be a good fit. I compare what high school say students learn to what colleges assume high school graduates retain, and I take that pretty heavily into account. I'm not interested in holding my kid to a superior standard, just providing a reasonable "translation" of natural learning into a simple, lowest-common-denominator sort of format.
Mostly, it's pretty easy. Natural learning really does lead kids in all sorts of wonderful directions! It even leads to a fair amount of intellectual rigor in terms of questioning sources, analyzing information, expressing ideas clearly, even examining the ethics of decision making. It does because natural learning isn't about doing just enough to pass a test, it's about following the rabbit trails of curiosity and discovering where they lead. So that even when the "subject matter" derives from fan fiction and video games rather than textbooks and approved reading lists, curiosity itself leads kids to develop the kinds of mental skills that schools work so hard (and often with such futility) to impart.