Semi-permanent adhesive-ness?

[sickofyourbs.livejournal.com]

So I'm planning on building/modifying a table for a train set for my 2.5 year old son. We want to get him a Thomas the Tank Engine set (he looooooves trains), and I have a coffee table that I'll be adding on to. I plan on putting hinges on it and adding two extra "wings" (what IS the technical term for those) so that it's semi-portable for when we move again. I want to be able to "stick" the pieces (buildings, track, etc) to the table, so he won't be able to remove them, but I also want them semi-removable so that we can fold up the table to move it. I was thinking heavy-duty velcro, sturdy enough to keep his little prying fingers from tearing it apart, but removable enough that I can take it apart when needed. Anyone have anything better?