Is there a way for a teenager to lose weight drastically without getting all of that excess skin?

No: The excess skin will be maximize by rapid weight loss. Drastic weight reduction does not work over the long term. Learning healthy lifestyle eating and activity is your best way to maintain weight loss and reduce the problem of excess skin. Weight loss should be no more than 1-2 pounds per week.

Slow wt loss: If the weight loss program is both workout and nutrition plus not to exceed 2pounds per week will prevent excess skin.