Walking with Bilbo was definitely a good choice for that age group:
even if they're not familiar with The Hobbit, they know that Bilbo was
the one to find the ring, so you can build a lesson off of that.
Perhaps your theme could be looking for treasure. Bilbo thought he was
on an adventure to find the dragon-wealth of the dwarves, when the REAL
treasure was the ring he accidentally found in the tunnels under the
Misty Mountains. The ring looked boring and nondescript at first, but
soon it became the key to the whole story -- and later to LOTR (though
in an negative sense). The Bible is the same way, except in a positive
sense. Our first impression of it is that it's boring and irrelevant --
not as exciting as the treasures the world offers. But once we start to
use it, we realize that it's the REAL treasure after all, the key to
all our adventures.
So as far as activities go, what if you recap Bilbo's story and then
take the kids on a treasure hunt, complete with a map ("X" marks the
spot!)? They must solve a riddle to figure out where to start (the
volleyball net, for example), then use a compass to take 12 steps west,
then 8 steps south, then 27 steps west again, etc., until at the end
they find a box with a Bible in it. There are all kinds of scripture
verses you could use -- perhaps print your key verse on tiny slips of
paper rolled inside plastic wedding rings from the dollar store, and
have those slips in the box too. They can wear the rings as a reminder
of the lesson. Voila! Sounds fun -- wish I could be there! :)
Sarah Arthur