Hi Shirley,
My 11 year old, seventh grade, son sleeps in every chance he gets, sometimes more than 12 hours! I have found that as soon as the last 3 hour bolus wears off, his blood sugar should be checked and corrected, if necessary. If the correction bolus, or giving of carbs, is accurate at that point, his blood sugar usually levels off near his target blood sugar number (we have his pump set at a target of 90).