I can remember when we were little my parents would get buckets and hang them in or around some trees, and we would watch as they filled up with what I thought then was water. I remember them doing this best one year for Tiffany's science fair project for school. Eric and I (well, mostly Eric) have now made maple syrup several times. I have had several friends ask me how to do this, and it isn't that difficult at all! You need to do this early spring, when the nights are still really cool, but the days are warming up. The first step is to tap some maple trees by drilling a hole into the tree and creating some way to catch the sap (Eric used a coupler with black pipe attached to it, where as my dad used tubing.) Then, catch the sap into buckets and when they are full, empty them and keep the sap cool.
After you have quite a bit of sap (I believe it is around a 40 to 1 ratio), then you boil it down until it is 7 degrees above whatever boils at. Dad and Eric started out with between 125-130ish gallons of sap, and ended up with a little over 3 gallons. It is so yummy!