Mark off a 1 square meter (or yard) section of grass. Scatter a selection of colored toothpicks in the marked off area – you will want to count the number of toothpicks of each color before you scatter them.
Provide a group of students with ~15 seconds to pick up as many toothpicks as they can find. Count and record the number of each color that was collected. Repeat this exercise several more times.
After returning inside, students can graph the data. You should find that the green toothpicks were found in smaller numbers, especially in the early trials.