Homework/study groups for kids, teens and students. Requirements by each age group. Meet at Libraries. Do homework, school projects, research & debate etc, depending on the group, plus friendly interactions so they make friends.
Robotics club. Can meet at Foxbury Commons or maybe you could set up a robotics lab at a science museum. Make, maintain and upgrade robots, scavenge or tinker for parts and socialise with other roboticists.
Occult clubs that do activities unique to themselves, socialise and have rivalries and alliances with other clubs. Hangouts and activities could be chosen based on whether they are openly occult or hiding their powers, have mischievous intentions or just need other sims for activities like duels or faster group potion making etc.
Sports clubs with rival teams for basketball, soccer, swimming, darts, ping pong etc.
Crafters, Work From Home and Freelance career clubs that can meet and do tasks together. Location and activities would be based on career but a few examples are Freelance Programmers meeting up at an internet café to work on gigs, Gardeners volunteering to maintain a community garden or Stylists, Knitters and Fashion Photographers doing their work at a Fashion House (retail clothes store).
