Always make sure the objects do not pose a choking hazard or have sharp edges.
A hallmark of a Montessori program for younger children is the "Treasure Box." This is something you can make on your own at relatively little cost. Again, the goal is to help your little one develop each of their five senses. The basket can contain items made out of wood, leather, fur, feathers, metal and any other natural materials. Always make sure the objects do not pose a choking hazard or have sharp edges. Also, avoid including plastic items in the box.