Of course, like a lot of kid's books, this shape is labeled a diamond, but in Montessori children are taught the proper geometric names of shapes. In this case, it's a rhombus. But when DJ was "reading" the book tonight he couldn't quite remember so he called it an Ovoid. I think he just likes that word.
So I suggested he pull out his Geometric Solids so I could remind him what an ovoid looks like. The curved shapes in this set (sphere, ovoid & ellipsoid) are his favorites because they have little pedestals to stand on.
After putting away the geometric solids, DJ pulled a drawer from the geometric cabinet. He doesn't usually pay the cabinet much attention but we were trying to get him to go to bed, so of course he was suddenly VERY interested in geometry! Above, he has what's called the demonstration tray, which has the introductory shapes, circle, square and equilateral triangle.
Then he pulled out the quadrilaterals with some real mouthfuls, parallelogram, isosceles trapezoid, and of course, there's the rhombus where we started!
At this stage, DJ is only meant to experience these shapes on a sensorial level and although I give him the names, he's not expected to remember them, (or even be able to pronounce them) for some time yet! Eventually, he'll use these tools in elementary to study geometry. For now, he's just having fun with them, and using them quite effectively to avoid bedtime at least for a few minutes.