My best advise for getting the kids in - PANDER.
Let the kids play leagues that sing to them, even if you have to bend your more classical or personal views of what Pulp "is". In our case my daughter went with a superheroine and a couple of Spyfi figs. While not exactly pulp, I at least made sure the weapons they carried fit the time, even if their costumes were a bit disco. Now, my daughter has a small league of three miniatures that she can manage and really get into.
When we get around to painting them, I'll maneuver her toward at least painting them in more pulpy colors.
It also doesn't hurt to get them into making terrain with you. Not only does it feel like arts and crafts time, but when they know it serves a purpose, they tend to want to see it fulfill that purpose.
-Eli