This investigation follows an elementary scientific method - students are given a question: Do M&M's or Skittles package their candy more reliably and consistently. Students make their own hypothesis, and then start their experiment. Each student should have a fun size bag of either M&M's or Skittles, can open the bag and start sorting their candies (make sure they wash their hands first!). Have students sort the colors, marking down which colors they have and how many of each, and then they tally the whole bag. Have students match how many candies they have with the serving size. If you get the fun size bags you'll have to keep the big bag they come in for the serving size information. Students write their data down on the sheet. Ask for student volunteers to offer their data to create a class chart. With the class information, have students create their conclusions.
Students can eat the candy when they're done!