I'm GMing a game were the setting is the fallout universe, all my players are vault dwellers and started the campaign underground, knowing nothing about the surface world. That mean that they're learning new things, on nearly every step.
On our first session, they've discovered mutants insects, ghouls, drugs hubs, and a ghoul city. They've learned a bit from everything mentioned above, everything looks like a discovery, but I'm wondering, Did they really just earned 8 exp just for discovering things on 4 hours of gameplay? or, I'm just been to generous with their earned xp?