a) build something with the 'big blocks' of wood?
b) turn over the tan and red sandbox and fill it with rocks?
c) play on the disassembled (green) fiberglass slide that your great aunt found at a yard sale?
d) drop rocks into the venting pipes for the furnace and hot water heater?
The really great thing about this type of activity? Return On Investment! A few minutes of plunking and rolling and rocks clinking together and THEN you get to spend Sunday afternoon watching Mommy and Daddy attempt to fix the problem.
Just in case anyone is interested: we ended up turning off the furnace and hot water heater, disconnecting the pipes in the basement (the only place they could be 'easily' disconnected), and then vacuuming out the pipes by duct taping an extra long hose to the shop vac. It made a HORRIBLE noise, but managed to remove all 60-80 rocks.
The backup plan was to run water from the exterior, down the pipes and into the basement. Thus, flushing out the rocks. I'm glad we didn't have to do that one, because the idea of me standing in the basement, water pouring out of the pipes, trying to catch it all in a trash can, yelling at Fritz: "Okay! Okay! Stop the water! Stop now!"?
Not so funny.