If there is a way you can tweak it for your current market and then expand it, that would be better — even if it takes more time up front — because you can use your existing client list.
If you start with a whole new niche where it doesn’t apply to home-schoolers, then you are basically starting a whole new business and it will require much more time.
On the other hand, if your product could apply to SOME home-school parents then you have some cross-over, and you can still leverage your current list.