How to mentor?

"3KNPen;c-16246276" wrote:
You can only mentor sims until they reach a certain level of the skill you're mentoring them in even if you're fully maxed in a skill. This 'causes troubles for the Bodybuilder Career where your daily requirement is to mentor people but finding people to mentor in athletic can be hard since most of the people you run into at the gym have already reached the skill level where it's no longer available to mentor them.

When I do the Bodybuilder aspiration, I form a club with myself and teen Sims (with some fitness skill (but too young to max out the skill). Then I go to the gym and call a club gathering at 4pm (since the teens are done at 3). Once I've finished the aspiration, I disband the club.