It was a kids cartoon. There were rectangular portals that opened on the floor and kids were abducted or could transport through them. In one scene I remember someone running into the room, seeing the portal and lifting the bed up just as the portal closed.
In another kid 1 says "I'll see you in class tomorrow", not knowing the other one is still trapped in the portal.
I can't remember the type of world the portals led to, other than thinking it was a typical 'volcanoish' hell.
I watched this in the 80s-ish. Perhaps 84ish around there; I can't imagine this was in the 90s.