Southpole Men's Relaxed Fit Sweatpants - Comfortable Casual Joggers for Lounge & Workout (Regular & Big & Tall Sizes) - Perfect for Home, Gym, and Everyday Wear

My son loves this brand, and he likes the elastic ankle or open but narrowish hem more than the jogger cuff. However, these specifically say not to use a dryer and to hang them dry, so you need to plan a little extra time. Comfy and relatively thick.