Another fun way to demonstrate cell proximity is by creating these fun summer bubble blow bottles. I saw another family having fun with these this summer and had to find out how to make them!
Cut the bottom off of a water bottle. Use a rubberband to secure a piece of terry cloth (washcloth) over the bottom of the cut opening.
Now dip the terrycloth bottom into a pan of dishsoap and water. Then blow throught the waterbottle top and watch a snake of bubbles form.