Sure they can. If you drink a can of soda, you get like ten teaspoons of sugar into your system right away, all dissolved and ready to be dumped into your bloodstream. Your blood sugar skyrockets, which signals your pancreas to squirt out a lot of insulin, which triggers your body tissues to consume the sugar quickly.
Twenty minutes later that sugar is all used up (in a healthy person, not a diabetic) but your blood is still full of insulin. So your blood sugar goes low, and you feel tired, cranky, and hungry. That's hypoglycemia.
It's thought that children get hypoglycemic more often and easier than adults. You know how little kids can sometimes just get into a bad mood and make a lot of trouble? Sometimes that's hypoglycemia.