This is a checklist showing hundreds of leisure pursuits. Feel free to use this in any way you wish and you may need to add to it as new interests are emerging all the time.
There are several ways you might use this checklist.
INDIVIDUALS: Use the list to help students identify what they are already involved in and what they might like to try in the immediate future.
GROUPS: In a classroom setting the students can be asked questions that help them process the list in more detail. Which activities are indoor/outdoor, costly/cheap, teams/individuals, easy/difficult, available locally/not available.
When suggesting to people to try a new activity, keep it simple. Help them make a plan that has a 95% chance of succeeding. If more than one student is interested in trying the same new activity, they could work together as a team. Encourage them to use internet searches to find local clubs or experts.
I spent six years at school in Belfast back in the middle of the last century (honest), and even then they had the custom of organising a hobbies exhibition every two years. This was an amazing event and we would see hobbies that did not normally surface in the daily life of the school. I recall a group of senior students who used to launch small rockets near Lough Neagh and they measured the distance travelled using on-board transponders. The model railway enthusiasts used to bring in all their bits and pieces to make the biggest train layout I have ever seen. Now there's an idea.
Why not try the checklist on yourself? This could be the start of a whole new area of interest.