Final answer:
The nurse should teach the adolescent with type 1 diabetes to aim for an HbA1c level of less than 7% to reduce the risk of complications and to maintain fasting and bedtime blood glucose levels within the normal ranges.
Step-by-step explanation:
When providing teaching to an adolescent with type 1 diabetes mellitus, it is important to establish management goals that include maintaining hemoglobin A1c and blood glucose levels within certain target ranges. The goal for hemoglobin A1c should be less than 7%, as this is indicative of better diabetes control and reduces the risk of diabetes-related complications.
Normalizing blood glucose levels is also vital, with fasting or pre-meal levels ideally ranging from 70 to 130 mg/dL, post-prandial levels (1-2 hours after eating) being between 100 to 140 mg/dL, and bedtime levels being well-controlled to prevent both nocturnal hypoglycemia and hyperglycemia.