C.W.
This is a awesome way to learn. Benefits vary from child to child. It is very hands on - great for children that are visual. It allows your child to learn using all styles of learning. I have heard so many positive things about Montessori learning. It is style that is best to start at a early age than going from a traditional school setting and then later say 1st or 2nd grade do montesorri style. I homeschool and have used many of their techniques especially in Math. You may want to research it online to find out more information or talk to other parents where you might be registering your child.
The school should be able to explain the difference as well and share the benefits. Blessings, C.