Making a volcano is a fun and easy science project for kindergarten and 1st grade students. I mean who doesn’t like turning fruit into an explosive volcano? Since this experiment uses minimal supplies and is simple, it is perfect for young students. Parents will have to assist their young scientists with cutting the fruit besides from cutting, students will need little assistance with the other steps. Students will also enjoy answering the question, which fruit makes the best volcano? Are you ready to find out? If, so check out this erupting fruit volcanoes fun science project for 1st grade below.
What is a volcano?
A volcano is an opening in the Earth’s crust. It usually looks like a mountain. When a volcano erupts hot gases and hot melted rock called lava escapes through the Earth’s crust.
Lava is hot, very hot. It’s temperature is between 1,300-2,000 degrees Fahrenheit. After lava flows out of the volcano it cools down and hardens into rock.
Making a volcano is a great experiment for 1st grade students. They are not hard to make and fun to watch.
In this fruit volcano experiment you will ask the question, which fruit makes the best volcano? Students will first turn a piece of fruit into a volcano and second make it erupt by combing and acid and a base.
What is an acid and what is a base? Keep reading to find out!

What happens when you mix an acid and a base?
When you mix an acid (in this experiment the acid is the juices of the fruit) and a base (in this experiment baking soda) it causes a chemical reaction. The chemical reaction is the carbon dioxide being released. In this experiment the carbon dioxide that is release when you mix the baking soda with the fruit juice causes the eruption.
You can try this with a variety of fruits. The more acidic a fruit is the better the eruption. At home, we made volcanos with lemons, apples and oranges.
Scientific Method
In this experiment we fill be following the steps in the scientific method. The steps include:
- Ask a question
- Form a hypothesis: Make an educated guess
- Conduct the experiment
- Gather research
- Conclusion
Question?
Which fruit volcano will have the biggest eruption? Meaning, which fruit is more acidic?
Let’s find out!
Materials needed:
Fruit: We used lemon, orange and apple. We had two of each in case we made a mistake.
3 tablespoons of baking soda
Dish soap (this is optional but makes bigger eruptions)
3 tablespoons of baking soda
food coloring (this is optional, we wanted colorful volcanoes)
Three paper plates
Knife (parent use only or parent supervision required)
Spoon
Hypothesis
My daughter Janelle, who is a 1st grade student thought that the lemon would have the biggest eruption. What do you think will happen?
Step 1: Making the volcano
The first thing you will need to do is make the fruit sit up on the plate without falling over. To accomplish this, have an adult cut the very bottom of the fruit off. Just enough so the fruit stands up. Do not cut it too deep, or the juice will come out.
Once each piece of fruit can sit on the paper plate without falling over, have an adult cut the top of the fruit off, you want to cut about 1/4 down from the top.
Next, its time to make the hole in the middle of fruit.
If you are working with a soft fruit such as an orange or a lemon you can make a hold by moving your spoon in a circular motion in the middle of the fruit.
If you are working with a harder fruit such as an apple, you will have to cute a hold in the middle using a knife. The hold should be about 1.5-2 inches in diameter. Once your fruit had a hole, you can move on to step 2.


Step 2: Collecting the Acid
Did you know that fruits such as lemons, apples and oranges are acidic? Acidic means having an PH of 6 or lower.
Scientists use a PH scale to tell how acidic something is. The scale runs from 0-14. Anything that has a PH of 6 or lower is acidic. Anything with a PH between 8-14 are considered bases. 7 is considered neutral.
Citrus fruits are acidic. Here is a list of acidic fruits:
- Lemons
- Limes
- Grapefruits
- Pineapples
- Peaches
- Oranges
- Apples
- Grapes
- Pomegranates
- Tomatoes
To collect the acid in this experiment, you are going to get the juices out. For softer fruits, you can squeeze them, for the harder fruits such as apples. You can use a spoon to scrape down the sides your hole in the middle of the fruit. Pour the juices into a bowl.


Make sure you collect as much juice as possible. It is important that the bottom of your fruit stays intact so that no liquid can escape the bottom. If you puncture the bottom of the fruit, you may need to start over.
Optional Step 3: Color and Bubbles
This is an optional step, I suggest you try it out because it adds fun and color to the experiment. Add a couple of drops of dish detergent in the center of the fruits hole. Next add a couple of drops of the food coloring and stir.
You can try this experiment using dish soap and color and try it without, see if there is a different in the eruption.

Step 4 Adding the Base
In this experiment, baking soda is your base. Add one tablespoon of baking soda to each of your fruit volcanoes.
Step 5 The Eruption
This is the best part of the experiment and the most fun for your little scientist. Slowly add the juice back into the fruit volcano. Make sure you add the lemon juice to the lemon, the apple juice to the apple and orange juice to the orange. Your volcano should erupt immediately.
Did your volcano erupt? Which fruit had the best eruption?


Conclusion
In our experiment, my daughter found that the lemon made the best volcano and had the biggest eruption
Variations:
There are many ways you can try this experiment.
Instead of adding lemon juice back to the lemon, try switching the juices. Did you notice any changes?
Instead of using the juices from the fruit, try using store bought juices.