Do your children like locks? When Caspar was young we put a lock on his cubby house as he loved locks so much. He always wanted to use the lock on our letter box. When he was a little older I gave him a lock tray using locks from around our home.
I wanted to show you Otis's lock box because if it wasn't for Montessori I would never have thought to give my child a toy like this. He can open about six of the ten locks. Inside there are compartments so it's fun for the child to hide things. Can we call it a practical life activity? It certainly keeps those little fingers moving, pulling, twisting... opening!