Student should be provided with graphics depicting animal cells and various virus families. The students should then be broken into different groups with each group having a different shape as their (triangle, square, circle) surface receptor. Students should be directed to use the shape of their group for the surface receptors on the membranes of the cells they construct. Then the materials listed above should be provided to each group. The students should use their creativity in using the materials to construct their cells making sure to include the cell membrane and nucleus. Once the students have constructed their cells, the students should rotate groups so that they are now using a shape different from what they originally had for constructing their cells. These new groups will choose a virus family that infects human cells and then start constructing their virus making sure to use the shape (triangle, circle, square) of their new group for their viral surface receptor. When the students have completed creating their viruses they should attempt to attach their newly constructed viruses to their shoebox cell membranes. Students should come to the conclusion that the shape of the receptors on their viruses and cells are different and therefore will not allow for the virus to attach to the cell. Students should then be allowed to investigate if their viruses are capable of attaching to any cell that was created by their classmates in other groups. Students should be able to find that the circle surface receptors fit together, the square surface receptors fit together, and the square surface receptors fit together. This will lead the students to come to the conclusion that in order for a host cell to be infected, the virus and cell surface receptors must "fit" in order for the virus to attach to the cell membrane.