Starting to get nervous

I've mentioned before that Galen is a little bored with kindergarten math. Well, today he stunned me by going through three entire math lessons in one sitting, at which point I stopped him. At this pace we'll be starting 1st grade math during or right after the holidays. I'm not sure if I should let him set the pace, or hold him to the one lesson a day the curriculum is designed for, but I do know that either option is going to be challenging for me.

With the first option I have to find ways to keep him challenged while we progress through the program topics at the suggested pace. This is doable, but will require a lot more work for me finding ways to do that. The second option allows us to work through lessons at his pace, speeding through areas that are no challenge to him and slowing down in areas where he might need a little more time. If we run into enough sticky areas the overall pace might not be that fast compared to the suggested pace, but I've already looked through everything I have (20 units through the course of the year) and I don't see much to challenge him in all but about 5 units - and that depends mostly on how fast he picks up on it. That includes the only supplements available at the kindergarten level. Thankfully grades 1-6 have more and better supplements designed to challenge advanced students (and they have one that provides additional practice to average students as well, but I doubt we'll need that).

The second option seems like the thing to do, but what do I do if he's worked his way up to levels that require more abstract thinking but isn't developmentally ready for it? I'm great with math, but I don't think I'm up to winging it in that situation. Of course I may be worrying about nothing. His current pace isn't likely to last all the way through, and even if it does it may be accompanied by the mental development needed to do the more abstract thinking required at higher levels.

I figured he'd be naturally gifted in mathematics given that his daddy is an engineer and mommy is a biology professor and mathematics geek, but I think I overestimated the challenge that Singapore Math would provide. I don't really expect anyone to have the answers for me - for starters not that many people even read my blog. ASU does have a graduate program in Mathematics Education though, so it's possible one of the faculty members there might be able to offer some advice.

Reading, on the other hand, is going at the suggested pace right now. I doubled the pace while we were reviewing short-vowel sounds and consonant sounds because he already had those down, but now that we're working on actual phonics-based reading skills we've slowed to the suggested pace. We're currently learning to sound out words by blending the sounds together, and reinforcing the idea of going from left to right.