On the question of how to teach him... maybe the answer is closer to home. Have you asked your DH? He did supply half of your DS' genetic material, after all.
My DW has homeschooled our DD9 quite effectively, but when she runs into challenges, I've been the one to solve them, because DD's learning style is so much like mine that I've frequently joked, "I have the user's manual to DD's brain."
DD says, "That's creepy."
Apart from solving individual challenges, I've also been able to give DW some general guidelines on what approaches work best.
She's definitely a visual learner, and when she was 3, she sat in my lap at the computer desk as I pulled up relevant images for whatever topic she had expressed an interest in, and talked her through what we were seeing.
