I think a private tutor, or mentor, is a good idea. Either now, or in a few years, it might be a good idea to call around to a local university math department and ask:
"I have a son who just loves math, and seems to be very advanced, would one of the professors please meet with him so that you can help guide us to what books we should share with him or which student we should hire to mentor him?"
Then once you've met one of the professors, they might be so tickled that they themselves volunteer to tutor. It's possible for a first grader to be ready for college level Math.
Meanwhile look on the Internet for 'Khan Academy' and 'Art of Problem Solving' - check locally for a 'Math Circle'
I would also ask the school if they do 'MAP' testing. If your local school doesn't do it, then call around if any of the other schools do, and will let your son sit in. What is nice about MAP testing is that it's on a computer and adjusts the level of questions based on if the previous answer was right or wrong. You should get a number that shows, up until about 8th grade, where your son is - and information about 'what to learn next.'
Your school district's website may have a page called 'scope and sequence' where they show which Math is expected to be learned in which grade. That can be enlightening.
I would also encourage you to read: '5 levels of giftedness.' by Deb Ruf
How is the speech going? Is he up to normal yet?
Love and More love,
Grinity
