Float or Sink: A simple science activity to do with your children [Activity]

Out for another walk…what to do?  Collect materials from outside and inside to conduct a Float or Sink investigation. 

My son Theo is five years old and is really into doing experiments.  Being a science educator, I should have many up my sleeve to share with him but, I’ll be honest, I’ve been drawing blanks!  Since I’m not a preschool teacher,  coming up with ideas that are at his ability level are really hard, and I’m also like every other parent working full-time out there right now and feeling overwhelmed with managing life (and then there’s my high expectations of making sure I’m holding true to the Next Generation Science Standards).  Phew. I decided to take a step back on this one and share with parents, teachers and volunteers a simple way to engage your preschool-age audience in a simple and fun investigation: Does it Float or Sink? 

The beginning of this investigation was sparked by the idea of boat making.  A boat needs to float in the water and potentially carry weight.  That is where our investigation started.  On your walk, the first thing to do is gather materials from outside.  This can be anything:  acorns, leaves, sticks, rocks, pine needles, etc.  You can then gather materials from the house like toys, cups, wax paper, tinfoil, newspaper, juice containers, etc. 

Start the investigation by making predications on what objects will float or sink.  Grab a bucket of water or simply fill your sink and begin testing! 

After sorting through your materials and separating them into a sink or float pile, think about which materials you have that float, but that could also be formed into a boat.  Perhaps then test out your boat with objects that sink to see how much weight your boat can hold.  Add a sail or not, and put it to the test! 

I videotaped the investigation with Theo and there were so many observations that I made and would love to follow up on.  As you watch the video, you can see how casual we are about testing.  Remember, he is five, so play is a great way to teach this age group.

If I were to delve into what Science Practices Theo was using, the most emphasized was the sub-practice associated with “carrying out an investigation” stated as: “Make observations (firsthand or from media) and/or measurements to collect data that can be used to make comparisons.” I think the second practice that was illustrated was “Asking Questions” especially with my facilitation as I demonstrated how to “ask questions based on observations to find more information about the natural and/or designed world(s).”

At the end, to improve upon our investigation, I would help him to compare same-sized objects that were made from different materials. Something like this may help Theo understand that material type (the density of the material) plays a role. This could help support Theo’s conceptual understanding of floating vs. sinking as related to material types.

It got interesting when we tested the wax paper boat, and the acorn was able to stay afloat on top of the wax paper boat but not on its own. That also seemed to pique Theo’s interest. I heard him saying at the end of the video, “can we make another one of those?” I can imagine a follow-up in which he’s exploring even more how much his boat can hold.  We ended up using a juice container made from waxed cardboard as our boat



Extension Field Specialist-Science Literacy
Extension Field Specialist, 4-H Natural Resources
Phone: (603) 641-6060
Office: Cooperative Extension, Taylor Hall, Durham, NH 03824