- Education and Science»
- Life Sciences
Kids Love this Gross Science Project on Digestion that Ends as we Make Poo
This is the Ultimate Gross Science Project: When Else Do You Get to Make Poop in the Kitchen
What could be more fun for kids than a hands-on science project teaching about digestion that ends by making a poo? Starting with everyday food and adding common household items like dish detergent and vinegar, we take kids step by step through the digestion process. The project uses a bowl to simulate the mouth, a potato masher for teeth, a blender for the stomach and a stocking for the intestines and anus. In about 30 minutes, they will have studied the digestion process from start to finish, learning and laughing all the way and finally squeezing out a small piece of "poop".
They may verbalize your thought "ewww, gross,' but afterwards, they can explain digestion. I honestly believe this is the best science activity we have done as homeschoolers. My girls even wanted to include their friends in this gross science project, and that is what you will see here.
We have repeated it three times over the seven years for two reasons. First, kids get different things out of it as they grow up and are better able to understand the digestion. And secondly it's fun to make poop.
Below you will find a bit on digestion, a video showing our project and finally step by step illustrated directions of the process along with a script, if you want to use it.
Get ready for some science fun!
What Is Digestion?
Digestion is all about breaking food down into tiny bits so it is small enough to travel around in your blood to feed your body and give it energy.
Some Additional Dictionary Definitions to Help Gross You Out Before We Make Poop
Definitions from the Apple Dictionary
saliva - noun
watery liquid secreted into the mouth by glands, providing lubrication for chewing and swallowing, and aiding digestion.
chyme - noun
the pulpy acidic fluid that passes from the stomach to the small intestine, consisting of gastric juices and partly digested food.
bile - noun
a bitter greenish-brown alkaline fluid that aids digestion and is secreted by the liver and stored in the gallbladder.
Small intestine - noun
the part of the intestine that runs between the stomach and the large intestine; the duodenum, jejunum, and ileum collectively.
Let's Take a Look at Our Completed Gross Science Project
As homeschoolers, this project was more than just science. We included a bit of film making. This video highlights our complete project from start to finish. The step by step details are below the video.
Video by Melissa Albom at age 12.
Watch the Complete Simulated Digestion Project Here:
Good Project? - What do you think?
Do you think this is a good project to teach digestion?
A Word of Caution Before We Begin
- This project can get quite messy, so keep a watch on it.
- ADD ONLY A SMALL AMOUNT OF LIQUID when needed. If you add too much, the project gets very wet, messy and it's more difficult to end up with a "solid" in the end.
Meet Our Science Team
What You Will Need for This "Make Poo Science Project"
- Food (it works great with 2 slices of toast and a can of spaghetti)
- Mixing bowl
- Potato masher
- Simulated Saliva (water/detergent)
- Simulated stomach juices (vinegar)
- Simulated bile (3 x food coloring)
- An old stocking with a small hole at the toe
- White tray or plate for collecting samples (Optional)
Where Does Our Food Go?
Let's find out . . .
The Digestive Process: Simplified
Before beginning children should have a basic understanding of the digestive process:
1: Food goes into our mouth, saliva begins to break it down and our teeth mash it.
2: It travels down the esophagus to the stomach, stomach juices break it down more. Now it is called Chyme.
3: Then Bile is added as it leaves the stomach.
4: Next, the intestines: first the small, then the large. The littlest bits of food are squeezed into the body to give us energy.
Step 5: What remains is pushed out through the anus as poo.
The Digestive Process
Start Here for Step By Step Digestion Simulation
A possible script is provided below:
The words to say are in Bold
The activities to complete are in italics.
Step 1: Into The Mouth
Put the food in the bowl (mouth)
Add water and detergent (saliva)
Use masher like "teeth" (chew)
Let's Make Poo - Step 1
SCRIPT: Simulating Step 1 with the Young Scientist: Into Our Mouth
Here we go - the first stop for our meal is our mouth. We will pretend this bowl is our mouth.
(Place food in bowl)
Here our food mixes with saliva, the wet liquid that is in our mouth. This saliva will begin to break down our food and our teeth (potato masher) will break it down even farther.
(Add just enough slightly watered down dish liquid to get the food wet).
(Use the potato masher to simulate chewing and break apart the pieces of food)
In our sample experiment we planned to use a New Zealand favorite, spaghetti on toast. We were out of bread on the day, so we substituted Weet-Bix (a popular breakfast cereal). It's important to select food that will be easy for the kids to mash up.
Step 2: Into The Stomach
Pour "chewed" food into blender (stomach)
Add vinegar (stomach acids)
Let's Make Poo - Step 2
SCRIPT: Simulating Step 2 with the Young Scientist: Into The Stomach
Imagine the food you chewed up has gone down your throat, traveled through a tube called the esophagus and landed in your stomach. We will pretend the blender is your stomach.
(Pour mashed food into blender)
Here stomach juices, a bit like acid, are mixed with the food. These stomach juices have an unpleasant taste and smell, and are what we have experienced when we have spewed up. We will use white vinegar to represent the stomach juices and the blender to do the mixing. After we mix it, our food gets a new name. It's now called chyme.
(Pour in a small amount of white vinegar as it will act as the stomach acids. Don't add too much vinegar, we want our "chyme" to be wet, but not liquid. Blend on low.)
Step 3: Getting Ready For The Small Intestine
Add food coloring (bile)
Stir with spoon (breakdown)
Let's Make Poo - Step 3
SCRIPT: Simulating Step 3 with the Young Scientist: Getting Ready For The Small Intestine
Next our food travels to the small intestines. As it leaves the stomach bile is added from the gallbladder (produced by the liver). This bile is important as it breaks down the fat in the chyme and also turns its color to brown.
We will use green and red food coloring to represent the bile.
(Add a few drops of food coloring to the blender contents. Pick opposite colors from the color wheel like green and red, if you want your end result to be a brownish color.)
Step 4: Through the Intestines
Helper holds stocking while chyme is poured in (into the small intestines)
Squeeze it through, allowing liquid to leak out sides (converting to energy)
Let's Make Poo - Step 4
SCRIPT: Simulating Step 4 with the Young Scientist: Through the Intestines
As it travels through the small intestines it nourishes your body. This is the fun part if you are a kid who likes to get a bit dirty. We will pretend this stocking is the intestines.
(Pour the contents of the blender into an old stocking with a small hole cut into the foot.)
The littlest bits of food are now digested small enough to be squeezed out through the tiny holes in the wall of the small intestine, into the blood and then sent around your body to give you energy.
(Slowly squeeze the chyme down from the top to the bottom of the stocking. The liquid will ooze out the sides as just like your intestines allow the vitamins from the food to circulate in your blood.This is a messy step, so you may want to put a pan under the work area)
*The stocking is perfect to represent the small intestines as the small holes in the stocking allow the moisture to escape. Do NOT use a new one, as you will want to dispose of it at the end of the project.
Step 5: Waste Out the Other End
Squeeze solid bits through hole at bottom of stocking.
Congratulations, You Can Make Poo!
The Final Step: Squeezing out a Poo!
SCRIPT: Simulating Step 5 with the Young Scientist: Out The Other End
The undigested food gets squeezed through the entire small intestine and into the large intestine where it will stay for about two days.
(Continue squeezing the food through the stocking towards the bottom.)
Finally, your body has used what it needs from the food. All of the remaining liquid has been sucked out from it and it becomes more and more solid.
(Squeeze the remaining bits through the hole you cut into the stocking)
This eventually is pushed out the anus (hole in the stocking), and we have poo!
Are You Going to Make Poo?
If You Like this Project, You will Love Totally Gross - The Game
A dose of gross and kids have more fun whiled they learn science. We love this game! It engages kids as they learn about all the major scientific disciplines. The game finds "gross facts and activities from biology to chemistry to zoology. As they play, kids (and parents) answer questions, learn interesting facts and participate in activities. It's all in the name of science!
Sarah Drew the Digestive Process
If You Loved This Project Check out this Gross Science Book
There's more to gross science than just making poo! I bought this book for my nephew many years ago and he loved it.
(poll added March 2011)
Did I Gross You Out?
A Few More Great Science Projects and Answers
- Does Toilet Water Spin the Opposite Direction Across the Equator?
Ever wonder if the toilet water really spins the opposite direction when we cross the equator? Here is the answer, with clear easy to follow images.
- How To Separate Water - Our Homeschool Science Project
Do you know how to separate water? Here are the steps to return water to is original form two parts hydrogen to one part oxygen. What a fun science project!
© 2010 Rhonda Albom