This is my second leprechaun trap I've helped my kids with last year we made one out of legos. This trap only took us about 45 minutes to think up and make so it should take you even less. ;) We just used a simple square box and reinforced one of the flaps with the other flaps we cut off, by gluing the flaps onto the back of the one remaining flap.
To make the crane we used a few pieces of scrap cardboard and to make them strong we hot glued a few pieces together so it could hold up the basket of gold. The basket is made from a green soda bottle cap and a strip of construction paper for the handle. To top it off we used my sons fools gold from a summer trip we took last year to trick the leprecaun. Hopefully it will work to catch him because we are tired of all the pranks he pulls every year at our house. I really didn't appreciate him dying our milk green last year or glueing quarters to our sidewalk.