The digestive system is a fascinating part of the human body. Kids can easily relate to the information as you teach them about how the mouth, stomach, intestines and other organs work together to digest the food they eat, providing nourishment and energy to their bodies. You can easily talk about how you feel after eating different foods, and engage them in a few simple activities to educate them about what goes on in their bodies when they enjoy a snack.
After reviewing information about the digestive system with children and showing them illustrations of every organ involved in the process, give younger children a word search that requires them to find digestive system terms you discussed. Terms like "bile," "saliva," "teeth," "liver" and "esophagus" should be included.
Describe the stomach as a mixer, and then show what it does by setting up blenders, some fresh strawberries, bananas and water for students to work in groups on making their own "smoothies." Pour the smoothie slowly into cups, explaining that this is similar to how the stomach slowly releases liquefied food into the small intestine. For younger children, put the fruit into a zip-up sandwich bag, adding some lemon juice to represent stomach acids. With the bag firmly zipped, let students squish and squeeze the contents. Explain that their stomachs do a similar churning routine to break food down.
Not So Small Intestine
Help students get an idea for how long their small intestines really are by giving each child a spool of string and a measuring stick. Instruct each student to measure out 22 feet of string and then cut it from the spool with a pair of scissors. Explain that this is how long our small intestines are. Take the students outside to an area where each one can lay the string out straight. Explain that food has a long way to go after it leaves the stomach before it gets to the liver. Talk about how food takes about four hours on this trip through the small intestine. Then, have students pick up their strings and arrange them into tightly packed bundles. Explain that this is how the small intestine packs itself into our bodies, just beneath our stomachs.
Sights and Sounds
Kids will enjoy recreating the sounds their bodies make as they process food. Engage the class in a discussion about what sounds they've heard their bodies make while they eat and digest their food. Mention chewing, slurping, swallowing, gurgling, bubbling and of course, passing gas. Set up digestion "stations" around the room -- mouth, stomach, intestines, liver and anus and have students rotate in groups through the stations, using their hands, mouths, classroom items and their imaginations to recreate the sounds associated with each stage of the digestive process.