As a preschool teacher I try to be aware of how my work might introduce or reinforce misconceptions in my students’ understanding of concepts. In the Perspectives column in the September issue of Science and Children, Michele H. Lee and Deborah L. Hanuscin write about common misconceptions about astronomy, A (Mis)Understanding of Astronomical Proportions? (pg 60-61).
They report on studies that have found that elementary school age children

• often have difficulty interpreting two-dimensional diagrams which represent three-dimensional space
• may become confused by ambiguous terms, such as “round earth” which they may think means disk shaped rather than spherical
• when explaining astronomical phenomena—students who were allowed to manipulate concrete objects produced markedly different student responses from children relying on words alone.

So I will use the word “round” to refer to wheels and plates, and “spherical” to refer to balls and oranges, make 3-D models with playdough instead of drawing diagrams, and provide materials for manipulation when children are asked to tell what they know. It sounds like fun!
Blowing bubbles is an activity where using the word “spherical” comes naturally. The bubble wand opening is a circle and the bubble is a sphere. Children can point to a ball or a flat round disk to show what shape they see when they blow a bubble.
Peggy