If desired, use 1-3/4 cups noodles from a 5- to 6-ounce can or package for the tombstones and use remaining noodles to make "grass." Place noodles in a large plastic or paper bag; add several drops green food coloring. Close bag and shake to color the noodles. For darker or more even color, add more food coloring and shake again.
If tombstones won't stand, prop them up with large gumdrops or other candy.