How old was your child when you explained how to do the math for corrections and carbs? And when did you trust them to do it on their own? My son is almost 10. I think I'm more so stopping myself from teaching him more so because I don't want him to have one more thing to worry about. As of now he uses his cell phone to text me from school or where ever he is with his # and what he is eating and I do the math and text him back. But I know at some point he'll have to learn. So I was just wondering what's a "good" age?