... thus tickling the fancies of ...

One possibility is that they find that someone - the landlord or another tenant - has stored some equipment in the basement, including (say) a whiteboard and an ink stained desk or table: that and (say) the fact that both have their school uniforms. Knowing that this is about students using their imaginations as a lead in to losing their virginity, it shouldn't take much of their imaginations to unleash that spanking scene. Just a thought ... 😉