The Same and Different Donut Game is a pre-school activity to practice identifying objects that are the alike and not alike. Kids compare donuts based on shape, color and combinations of shape and color. After all rounds have been...

At this site from The Franklin Institute you can practice classifying objects according to physical structure and characteristics.

Students go outside take a closer look at leaves on a tree. The students collect leaves of different shapes or colors, and then sort into categories, and compare and contrast them to leaves that are non-native to Minnesota.