Montessori Materials can be very expensive. Traditionally they are made of wood and are very high quality. But many of the materials can be made at home and the same goals can still be achieved. That being said, there are a few materials that are just not cost or time effective to make yourself. One material I recently purchased is the Pink Tower. This is a sensory activity that teaches order, big, bigger, biggest, small, smaller, and smallest. Of course since all Montessori leaning is child guided sometimes other lessons can be learned as well.
At the moment she is still bringing the pieces to me, but it is the beginning of a learning process.