Tag Archives: sink or float kindergarten

Simple Science Project For Kids: Float or Sink

I love float or sink experiments. They have so much learning potential, are easy to set up, and offer different variations to sneak in STEM skills. The overall aim of this simple science project is to find out if objects float or sink. Kids love this because it is simple enough that they can do it independently and even draw conclusions by themselves. This helps them build confidence in their abilities as curious little explorers. 

simple science project float or sink

I can’t remember exactly when we started doing float or sink experiments with our oldest but I know we have done it a lot, in many different ways. At first we used her toys in the bathtub to see if they would swim or dive and eventually the proper vocabulary found its way. Developing scientific vocabulary in kids is such a great way to engage them in STEM. If they build this vocabulary around fun and hands-on experiences you are making it easier for them to better understand the concepts. Rather than explaining what float or sink actually means they are observing and testing for themselves and this simple science project is just perfect for that!

Simple Science Project For Kids: Float or Sink

There are many ways to do this project so first I will share different variations you can pick and choose from. Then I will give you an example of how we made our own simple science project and incorporated STEM learning with float or sink experiments. However you do it, remember that if you are combining young kids and water things are bound to get wet! Try to plan to do it outside or prepare a space that can get a bit wet so you are not worrying about this all the time. So here we go…

There are basically two ways to test if something floats or sinks:

  • Drop it in a bowl full of water
  • Place it in an empty bowl and fill the bowl with water

Questions you can ask to get your kids’ minds working:

  • What happens to an object when it floats/sinks?
  • Does it stay on the bottom?
  • Or does it stay at the top?
  • How can we find out if something floats or sinks?
  • For older kids: with your eyes closed, how would you find an object that floats/sinks?

Different ways of observing and working on STEM skills:

You can do a number of different things when you are engaging with your kids in this simple science project. From letting them discover and experiment by themselves, to guiding the activity a little. I always love to try a bit of both and observe my kid to see if she is up to being guided. Most of the time she will follow my lead but many times she just wants to do her own stuff, and that is totally fine too! So here is some inspiration if you are looking to guide the activity:

float or sink

Sorting and categorizing

This is a great STEM skill to practice. The obvious categories are float and sink but feel free to come up with more! Have two containers with the words float and sink and have them sort and categorize them either by testing first or by guessing and then adding water to see if they were right.

Testing, observing, and drawing conclusions

Have your kids test the different objects, observe and comment on what is happening. We discovered that green pine cones sink but brown ones float so it is not possible to say that pine cones in general float, which was my first thought! I love learning new things with my kid and showing her that I don’t know everything. I hope to foster a love for learning and a tolerance for making mistakes and not having all the answers right away.

Making hypotheses

Gather all the materials and have your kids make a hypothesis, a statement that needs to be proven. Set up an experiment to test the hypothesis and see what happens. 

Math

We can use this simple science project to sneak in some counting practice. Find out how many objects float and how many sink, which category has more items? Use 10 objects and work on ten frames. Keep a tally board while you are testing. Give each kid a clipboard and paper and have them keep count (tally) as they test, this is true scientific research!

Develop scientific vocabulary

When doing projects like this one always remember to talk to your kids about what is happening. Use the scientific words and help them build their vocabulary through hands-on science projects like this one. Explore what it means to float or sink, use other catergories such as size, weight, shape, color or texture. Basically it is important that you talk with your kids about what you are observing.

science float or sink

I hope these ideas give you some inspiration to explore with your kids and create your own simple science project for testing whether things float or sink. If you still want some more guidance and want to know how we did it keep reading. My kid and I were entertained for over an hour! Feel free to do it like we did or find new ways that better adapt to you and your family.

Our Float Or Sink Simple Science Project

Materials

  • Natural materials
  • 2 bowls for sorting/categorizing
  • 1 large transparent container for testing/observing 
  • Paper and pens
  • Water
natural materials

Simple Science Project Steps

Here are the steps that we followed to experiment with natural materials and the concepts of float or sink:

1. Gather natural materials

This is one of my favorite pre-project activities! Go on a nature walk and collect some materials, be sure to collect a bunch of different things and explore as a family. 

2. Create a sorting station

Lay out your natural materials, take out the 2 bowls of sorting and label them. I used 2 different bowls and different colored paper for the label to make it easier to sort and categorize. Prepare a testing container full of water and let your kids go ahead and test the materials and then put them in the right category. Observe and talk about what is happening. Use scientific vocabulary.

3. A bit of play in between

It’s good to not go from one activity to the next but rather to let our kids explore a bit by themselves and go off topic a little bit. Sit back and just watch your kid play a bit, comment and observe with them.  

4. Involve the senses

Add different materials into the testing container and have your kid find different objects while they keep their eyes closed. See if your kid can find something that floats/sinks and use this time to ask some questions:

  • Where can you find different materials if they float or sink? 
  • Top or bottom of the container? 

5. Finish off by testing in a different way

Ask your kids to sort the objects again without testing them first. They should try to remember what floats and what sinks. Once the natural materials are sorted into both bowls ask them what they think will happen with the materials that sink/float? Then fill the bowls with water and find out if they got them right! 

simple science project

As I said before, feel free to do this float or sink experiment following these steps or create your own project using this information as inspiration. It is so simple and yet so entertaining for young kids and toddlers that I’m sure that once you discover it you will be doing it more than once!  

Summary of STEM Concepts and Skills for the Float or Sink Simple Science Project:

  • Sorting and categorizing 
  • Making hypotheses 
  • Testing
  • Observation 
  • Math/counting 
  • Developing scientific vocabulary 
    • Float/sink
    • Weight: Heavy/light
    • Size: Big/medium/small

If you’ve made it this far, congratulations! I know that was a long post for such a simple science project. But that is the beauty of this project, it has so much STEM learning potential! Hope to have inspired some float or sink moments at home with your kids. Check out this other lovely float or sink experiment if you want to go into the topic of density.

More Fun Activities and Games:

float or sink

STEM Experiment: Scientific Method Float or Sink Activity

Oh the scientific method! Such a structured way to exploration but so helpful when taking on a big scientific project. Scientists and researchers use this method when trying to answer questions about our world. Following the scientific method allows researchers to have a guide that helps them organize all the information. Because let’s face it, nowadays the information at our fingertips is so huge! With this STEM experiment, you can help your children get an understanding of using the scientific method in a fun and educational way.

**Check out our Simple Science Project For Kids: Float or Sink for a simple play-based version of the Float or Sink experiment! Perfect for younger kids or if you are looking for a less structured activity.**

STEM experiment Scientific Method

Having a tool like the scientific method is very useful. And introducing it to your kids will help them with problem-solving and analytical skills. It will give them a way to structure their thoughts when problems arise. It also shows them to take their time to think about the problem and analyze different perspectives before choosing the best solutions.

Some Background Information

The scientific method is used by scientists to structure their research and make the process of discovering something more efficient and effective.

The steps to the scientific method are the following:

  1. Question
  2. Research
  3. Hypothesis
  4. Experiment
  5. Analyze
  6. Conclusion

As you can see, there are many steps before starting any experiment. By researching and writing down your hypothesis first you will be able to set up the perfect experiment to answer the question. You will also have some background knowledge that will help you when doing the experiment.

STEM experiment Scientific Method

STEM Experiment: Let’s find out the Answer to…

The Question

So here is a question for your children:

Why do you think things float or sink?

They probably have some ideas and answers for this. Encourage them to write down their original thoughts so that you can compare them once you are done with the STEM experiment.

Here you can find a free printable to fill out as the experiment goes on.

Time to Research

Research is usually done by reading and reading and more reading of scientific papers, journals and relevant material. We are not going to do this 🙂 We will move the research along by asking our kids some questions. So let’s get your kids brain to work a bit:

  • Think of objects that float/don’t float, what are they made of? How big are they?
  • Do you float in water? Can you make yourself float more or less? (By filling your lungs with air and holding your breath you will float more)
  • Show them a list of materials, do you think materials matter?
  • Show them different sized objects or images of objects, do you think size matters?
  • What other things do you think affect the ability of an object to float or sink?

Write down a Hypothesis you want to test

Now that you have brainstormed about why an object floats or not you can make a hypothesis or more than one! But first, what is a hypothesis?

  • A hypothesis is an idea or explanation for something that needs to be proved
  • A hypothesis tries to answer the question of your research (in this case, why do things float or sink?)
  • A hypothesis is proved through experiments and testing

Some ways you can express your hypothesis:

  • Things made out of _______ float/sink
  • Things that are ___________ float/sink
  • Floating depends on ______________

Time to test those Hypotheses

Once you’ve made a hypothesis, ask your child how you could test it. Here are a few examples of experiments you could do with them but feel free to come up with your own!

First step in any experiment is to gather the materials you are going to test and any tools you might need. For any experiment you are going to need:

  • Objects to test (different sizes, materials and shape)
  • Water, in a bucket, in the sink, in the bathtub, in a small outdoor pool
  • Paper and pencil to write down your findings

Ways you can experiment and make your children think about the hypotheses:

  • Categorize the objects you have collected and test their floating ability by pairs:

           ○ same material, different size

           ○ same material, different shape

           ○ same size, different weight

  • Get plastic containers and fill them with different materials and test the floating capabilities, for example:

          ○ empty container

          ○ container filled with cotton (what happens when cotton gets wet?)

          ○ container filled with sand

          ○ container filled with water

          ○ container filled with sticks

          ○ container filled with coins

          ○ container filled with stones

  • Do the same with a glass container

There is a list of materials and object ideas in the guide for inspiration. Let them experiment and play 🙂 there is no rush to finish the activity! Don’t forget to write down your findings so you can analyze them later!

Let’s analyze those Resultats

Now it’s time to look back on your STEM experiment and the results to see if your hypothesis was correct. You can ask the hypothesis back in question form and see if the results support it! Other questions you can ask to discover why certain objects float:

  • Does wood/plastic/metal/stone float?
  • Does shape or weight matter?
  • What containers could float? Which ones would sink? What was inside of them?

Conclusion Time

So did you find out why things float? Did you test your hypothesis? Did you get some fun ideas about other things you could test with this method? Did more questions pop up as you experimented? Welcome to the STEM world! The questions never end 🙂 and this is oh so important for your children to experience. How to answer questions using the scientific method is a must in the STEM world. If you want a more detailed answer to why things float you can download the printable guide, there is an explanation at the end. But I’m sure that you will have a pretty good idea about the answer from all that scientific experimenting you will do 😉

So to finish up the activity you can talk about what you discovered and if there are more things you would like to research together. If you have any topics you would like me to cover just comment below and I’d be happy to write a post about it in the future. I hope you enjoyed this activity and had fun experimenting and discovering how our world works.

For more information about STEM and how to transform your STEM activities at home, check out these posts:

Check out other fun STEM activities to sneak in some STEM learning:

Happy STEM learning!