You certainly have a lot of background and experience, so much of what I have to say may be a repeat of what you already know or do. But I just want to mention few thoughts. Just disregard stuff you already know. You are probably already a master at so much of this!
1) I agree strongly on the idea of pre-bolus. But I want to add, that you can be even more aggressive when you are at home, are around him, or when you have food easily available. And be more careful when he is at school, or aren't near your own fridge. Ideally, his BG will be on its way down and just getting close to low when he gets his first bite. That timing varies for everyone, but that's something you should experiment with, and can even use extended bolusing to make it just right. He can have a meal with normal carbs and not spike, but it just takes practice.
2) Along the same lines, when you bolus, you can be more aggressive with the amounts when you are at home, because you can easily correct that low if you catch it in time. And a little higher bolus, when used with a supplemental snack a little after the meal, will also help reduce the spike later after the meal.
3) Taking care of a low BG at home doesn't have to be a disaster. It can just be an opportunity for him to have a small treat, or something he enjoys. It doesn't always have to be 5 ounces of orange juice given like it is medicine! It can be something pleasant, which will bring his BG up just the same. Lows can be dealt with quicker than highs. That's the way I do it, just my preference. But it can be viewed as an opportunity for something tasty, which makes it not seem so bad.
4) If he isn't already, involve him in the process. I took over it pretty early, and when I left home it wasn't so hard, because I was ready. I think that is a very important thing to do for him.
Sorry, I am going on a bit. I am passionate about wanting to help the young ones have the best.