Because of an overabundance of rain this summer, our grass is still spring green and growing inches overnight. This kid has mowed 2 yards every single week this summer (in nearly 100-degree temps). And while he might hate it, he still does it (sometimes with a whole bunch of complaining and always with a break every 10 minutes). He got paid for 1 yard, but ours is all free labor. It often feels like more trouble than it's worth to make him mow the yard. Seriously, it often takes a superhuman effort to show empathy and support in the midst of the complaining, but let's be honest - I complain my way through hard things just as often.
It's good for him to know he can do hard things, and when he finishes, the sense of accomplishment just emanates from him.
Along with the sweat.
(I have never, ever, ever sweated this much.)