OMG. You were the one that got me hooked on those. Disregard... and you should be ashamed of yourself. I'm like an addict for those things now, never mind DS5.
I thought about your issues some more, and realized they are the same ones I'm facing right now, partly. How do you order activities for an asynchronous little one, while letting them pursue their interests too? I think that's why I started scanning everything in, so I could easily change the ordering on things.
I have a file-system folder of gigabytes of electronic documents, and they're organized by area, level, source, and description. I can pick and choose certain things out of their natural sequence, and move them so that I don't hit them again later, and move things out of the way that I think he'd find boring too. I can also put things aside in a "skipped" place to revisit later (I may not actually ever use them, in which case I put them in the "done" place).
So if you were to do something like that, it would take cutting out the sheets from the Singapore Math books, but you could combine them in one place with material from other sources and reorganize to your heart's content, and keep track in a less messy way, maybe, than shuffling paper or keeping notes.
In any event I hope I didn't come off as lecturing before. I think it'd be wrong to deny your daughter the chance to do what she likes best, and I can think of plenty of avenues of investigation her interest in coordinates and geometry, for example, could open up for her.
