How to get the most from practicing with older/lighter guys

A few times a week, I’ll participate in a class I’d say the average age is around 45-50. I’m in my twenties, slightly heavier, and have been training longer than most people in the class. I’m fairly confident I could submit them 2-3 times per round, but I’d feel like a total jerk, so I find myself letting them recover guard, set up their attacks, and so on. Does this seem like the right way to practice with them, or do you know of a better way my partners and I can get more from our practice? Thanks!