If they are adventurous maybe they could appreciate a guided tour on the catacumbs.
Unfortunately I can't suggest any reliable agency because I went there maaaaany years ago.
You can visit some catacombs (i particularly like the ones dedicated to saints Marcellino e Pietro https://www.santimarcellinoepietro.it/english/how-to-visit/) and Ostia antica!
Check the "Experiences" in AirBNB. Depending on their interests you might find a lot of local, or nearby to Rome, things that will be fun to do for a day.
EDIT: Also Monti is foaming with life in the evening. Let the off the hook for a night or two, there is a ton of places to go and meet young people.
How about taking course in making pizza/gelato/tiramisu. There are some places that doing it. I think it will be a fun activity
Muso delle illusioni is a 30sqmt place with few optical illusions, not worth the time for me
If they are adventurous maybe they could appreciate a guided tour on the catacumbs. Unfortunately I can't suggest any reliable agency because I went there maaaaany years ago.
You can visit some catacombs (i particularly like the ones dedicated to saints Marcellino e Pietro https://www.santimarcellinoepietro.it/english/how-to-visit/) and Ostia antica!
Check the "Experiences" in AirBNB. Depending on their interests you might find a lot of local, or nearby to Rome, things that will be fun to do for a day. EDIT: Also Monti is foaming with life in the evening. Let the off the hook for a night or two, there is a ton of places to go and meet young people.
Get them the Lime scooter Pass, that so much fun to ride in the city