Honestly, "fooling around" isn't sex to me either. Touching, kissing, hand jobs, and dry humping are just not sex in my head or my heart. ... But don't feel that you need to educate your boy out of his beliefs. They aren't necessarily wrong. You just need to be considerate of his definitions as well as your own.
This. If I were in his place and that's all that had happened, I'd say we hadn't had sex. If that were to continue for any length of time, I'd also conclude that there wasn't any real interest and walk on.
So I think his definitions are just fine for him and he doesn't need to be "educated" to change them.
When speaking of various forms of non-monogamy...it ain't poly if you're just fucking around.
While polyamory, open relationships, and swinging are all distinctly different approaches to non-monogamy, they are not mutually exlusive. Folks can, and some do, engage in more than one of them at a time--and it's all good.