One characteristic that sets Montessori schools apart from other schools is the use of practical life materials. Young children have a natural inclination to explore practical life skills like washing dishes, pouring, scooping, tweezing, spooning, etc. Using real materials like wood, metal, and glass helps the child to be careful and controlled. When you give a child a glass cup, they know you are trusting them to be careful and use it with caution. Children build confidence and gain respect for the materials they are using when they are real.
Using real materials in the Montessori environment also gives children actual hands-on experiences. If we surround the children with plastic materials, we are depriving them from the lesson of cause-and-effect. For example, if the cup always bounces when it falls instead of breaking, the child misses that opportunity to learn from their mistakes and to try again. So next time, the child is more likely to remember to put the materials on their work mat in an appropriate area so that they are free to use the materials without breaking them.
Montessori classrooms strive to provide real materials in a safe and practical manner. The goal is for children to develop real skills and habits for living in the real world.