Sorting and Matching Shells and Rocks

A few days ago O brought me 2 conch shells, and she said "niney (tiny)" as she handed me the smaller one and "big" as she handed me the big one. I told her that was a great idea for a montessori work. I gathered several shells and rocks that were big and tiny and put them in a basket together. I showed O how to put the big shells and rock in one basket and the tiny ones in the other basket. She caught right on and enjoyed this sorting work.
After she finished sorting the shells and rocks, I showed O how to match the big shells/rock with the tiny shells. She matched them quickly and then she was "done." (she loves to announce when she is "done!")