Illustrate the concept of cell division by talking about how a wound heals. Talk about how a paper cut heals by the process of cell division so the cut edges can come together. Explain how mitosis enables body growth and wound repair. Show pictures of babies transforming into adults to demonstrate the need for mitotic cell division.
Ask students to scrape some skin cells into a petri dish. Have them place the skin cells onto a slide that can be viewed under a microscope. Ask them to view the cells. Explain the concept of how cells know to stop dividing when they are in contact with each other because of "contact inhibition."
Illustrate the concept of why cells must divide instead of just growing larger by illustrating how surface area and volume change when cells divide. Ask students to determine the volume and surface area of two identical boxes. Compare these numbers to the volume and surface area of a box that is double the size of the two identical boxes. Explain that if a cell grows the food coming in through its surface area is not enough to support the cell's growth whereas if a cell divides, the surface area remains sufficient to support the cell's volume.
Ask students to draw the different phases of mitotic cell division. Ask them to demonstrate the changes in the chromosomes, nuclear membrane and other parts within the cell. Have them provide a summary of the cell cycle. Choose the top two illustrations and ask the students to present their illustrations in class.