If you do letters of the week with your tot then adding a sensory bin with things that start with that letter is a great way to make the learning stick! Here's our Letter M Sensory Bin:
As you can see, the base material was marshmallows. Then I added in some things that started with the letter M, as well as a magnetic letter M and a block letter M to show the letter itself. I added a felt Madeline doll, a Little People character named Micheal, a maraca, two mice from a board game, a large coin for money, a pretend muffin, and a musical note I cut from black paper.