Here is how the tray looks on the shelf.
The child turns each cup in the stack over in a row. Then they spoon each marble(from a cheap Chinese checkers game) into the cups while sorting the colors.
When they are done, they gently pour each cup back into the dish and stack the cups up.
Then they return it to the shelf the same way they found it:)
I love the sensory stimulation in activities like this, the sight of the colors, the sound of the balls clinking one by one! Love it!