This activity worked great for tonight because we didn't have a lot of time at home before the kids' bedtime.
We started by tracing one of the shamrocks from our activity wall: http://workingmomwonders.blogspot.com/2013/02/st-patricks-day-pot-o-activities.html
The boys then set out to find "green" things from magazines. They also cut out shapes from different shades of green tissue paper.
Then they pasted the green shapes onto their shamrock. That's it...project completed. (Well...except for the picture of the Geico gecko I have to find tomorrow for David's collage--the four-year-old. His brother has one on his collage, so David thinks his won't be complete without one either!)