The other nice thing about this: my mom is starting to help me 1-2 afternoons a week when I need it (I'm on an informal order of rest for the remainder of the pregnancy). And this past week Sheridan would cry on some days when I would pick him up (because I wasn't my mom - he LOVES his Nonna). So, I can add my mom on the days she will come so he can know on what days to expect her, and on what days he should expect me (and hopefully decrease his disappointment at plain ol' mom walking in the door).
I'm sure preschool and kindergarten teachers will have plenty of critiques of my method (and feel free to tell me how to improve it), but I'm not trying to do anything rigid here. Just taking advantage of what seems to naturally interest him, and help him learn more about it.
One final note... I had to move his beloved 1-20 number line to another location to make this fit in our living room. I've wanted to take it down numerous times, but every time I think about it, he starts using it for a new skill - lately it's been counting backwards from 20 to 1. So, back up it goes in our hallway, and my house continues to look more like a preschool than a home. But I'm ok with that.