As a kid Jim loved playing with those cardboard blocks with the somewhat inexplicable brick pattern printed on them (bricks made of mini bricks?). He had dreams of owning so many of them he could build a big, somewhat perilous ediface. That dream lives on today.
So, I started looking for cheap blocks to build "Ranger" (in this case- Jim) a huge collection of architectural materials. Amazon has quite a few options, but they were all too pricey for a cheapskate like me.
Google led me to the always helpful Berkeley Parents Network and their commentary on brick acquisition. Their advice on purchasing bricks through Lillian Vernon's catalog look great, but the June 1999 tip for making cardboard bricks with old milk cardboard cartons captured my imagination.
We had to buy half-gallon milk cartons because our local stores only carried organic milk in that packaging. My vegan parents had ample soy milk cartons and we love acid free orange juice (again, a beverage only sold in half gallons here).
So we rinse, cut, and wash our empty cartons, and then assemble them into individual blocks. The process is pretty easy, but cutting the cartons evenly can take a bit of technique.
Start by piercing the container on the side opposite the pour spout at approximately the location of the pour spout. This lets you have a jagged entry mark without marring the clean cut of the carton.
Cut downward at angle to sneak up on the fold line. When you reach the fold line, cut along it for a nice, even edge. It you happen to screw up an edge monumentally, make that the inside carton when you pair them.
Slide two cartons together, and presto- one water resistant building block! Soon you'll have enough for a whole playgroup. Don't like the patterns? You could cover them with contact paper or standard paper that your kids can decorate. Me- I'm lazy, so my son will get to appreciate the joy and value of reuse.
Jim recommends creasing the long sides of the carton to flatten the sides of the block- making it more stable for stacking.