Monday, October 7, 2013

Float or Sink

This Rubbermaid 2.5 quart food prep container is the perfect size for this tabletop work.
 Science lessons can be so simple!  "Float or Sink," for example, is a simple work that "Alleluia" loves.  All that you need is:

  • Clear, deep plastic tub (at Sam's you can buy these in the food prep aisle)
  • Basket to hold items to be tested (mine was less than a buck at Target's on clearance)
  • Towel to put under your work area
  • Index cards labeled "FLOAT" and "SINK"
  • (Optional)  Child-sized apron
  • Random objects to test, such as:
Pine cone, buckeye, maple tree seeds (aka "helicopter seeds")
Tops to the milk or OJ containers
Cork (mine is a coaster but you can use a good old wine cork)
Wax candle
Styrofoam (salvage from a box)
Ping-pong ball, other balls
Various floating toys (such as a fish taken from our toy fishing set)
Painted wooden block
Soap (both Ivory and another kind of bar soap)
Coin (beware of choking hazards, though!)
Jingle bell, paper clip
We've added things to our "Float or Sink" basket over time.
You can lay the index cards out on the towel to separate two columns, one for items that float and one for items that sink.  Talk about what kind of things float first, such as things that hold air, things made of wood, etc.  Then ask the child to predict whether the item will float or sink.  Sometimes you'll be surprised yourself!  You can introduce the term "buoyant" and "gravity" and "surface."  Older children may be interested to note that while a bar of Ivory soap floats, most others will sink.  Why?

Do you have any other ideas for items to put in our basket?


  1. So why does Ivory float?

  2. I'm glad you asked! Check this out:

    (Long story short: it's air.)