This activity has students randomly place chromosomes during metaphase I of meiosis. Students manipulate maternal and paternal chromosomes based on the roll of a die or flip of a coin (both versions included). This activity only uses 10 pairs of chromosomes (rather than the 23 that humans have) but even with less than half, there will be a huge amount of variety in the way different groups randomly lay out their chromosomes. This can lead into a discussion of how many different combinations there would be with 23 pairs (8 million plus!).
This is a relatively quick, but very concrete way for students to see how the random arrangement of chromosomes during metaphase I can lead to a huge variety in traits among organisms.
The activity includes a student worksheet and chromosomes to cut out and manipulate. There are various forms of the worksheet depending on whether you have colored paper available or not at your school.
Check out my other meiosis resources:
Mitosis vs Meiosis Pre-assessment Worksheet FREE!!