Discussion in 'Primary' started by taspat, Jan 27, 2011.

1. ### taspat

Hi, could somebody please help me. I need to explain concave and convex to year 4 children. I'm a trainee teacher, shapes isn't my strong point and I want the children to be able to understand it. Is there anything I could say to help them explain it rather than simply saying and showing that the concave shapes cave in?

Thanks

2. ### taspat

Hi, could somebody please help me. I need to explain concave and convex to year 4 children. I'm a trainee teacher, shapes isn't my strong point and I want the children to be able to understand it. Is there anything I could say to help them explain it rather than simply saying and showing that the concave shapes cave in?

Thanks

3. ### Kimchi_Pickle

I suggest spoons - everyone loves spoon reflections!
They should be able to work out that upside-down reflection is concave, and stretchy reflection is convex by fiddling around with the spoons and flipping them.

Maybe a convex/concave hunt - can they find the shapes in the classroom?

4. ### Little Tigger

http://www.mathopenref.com/polygonconvex.html
A nice flash illustration where you can drag the points of shapes to see if they are concave or convex.
We did sorting shapes according to properties e.g. symmetry, angles, concave etc. The children showed what they had learnt by sorting them onto a Carroll Diagram.
LT