Multi-age classrooms
All Montessori classrooms are comprised of three year ranges. There is a 3-6 year old class (primary), 6-9 year old class (lower elementary-equivalent of 1st thru 3rd grade), and 9-12 class (upper elementary-equivalent of 4th thru 6th grade). (Some schools will have additional programs for infants, toddlers, and middle schoolers.) The older children gain the experience of teaching the younger ones, the younger ones look up to the older ones, and the teacher only loses 1/3 of the class to matriculation each year allowing for a stronger classroom community. Multi-age classrooms are more reflective of the rest of society too. Don't we work and socialize with people of all ages?
Individualized instruction
In a traditional classroom, there are 30 odd students who have an age in common, but are of varied abilities in each subject. Regardless, a teacher must teach the same lesson to the same students at the same time. Inevitably it will be over the heads of some, boring to others, and right on target for a few. In a Montessori class, the teacher only gives lessons to 1-5 students at a time based on their individual levels. Maybe the day will begin with a lesson on fractions for a group of one 1st grader, three 2nd graders, and one 3rd grader, followed by a lesson on nouns for two 2nd graders and three 3rd graders. Meanwhile, the rest of the class is working independently on things they have already had lessons for. I know some traditional classrooms are moving a little bit in this direction, and i think that is great!
Student-led Learning
Montessori philosophy teaches that humans have a natural love of learning. We don't have to give walking lessons to babies; they are passionately driven to learn and when biological ability meets cognitive capability meets practice, they walk! In the same vein, students learn most effectively when they are actually interested in something and it is the "right" time for them to learn it. It is the Montessori teachers' job to observe students so that they can determine when that time is. Students will spend their day attending lessons they are ready for and doing follow up work on lessons they have had. The order in which they complete work and the amount of time spent on it is up to the student. This is not to say that a student might spend an entire school year doing nothing but studying the periodic table (though, would that really be so bad?), but they might be fascinated by the periodic table for a few months and the teacher will be tasked with finding ways of teasing out related activities. Maybe they will research chemists (history, language, and writing) and perform experiments (math and science).
Concrete learning
All Montessori lessons are given with an accompanying "material" which demonstrates the target concept in a visual and tactile manner. When a child is introduced to arithmetic (usually around age 4 or 5), they will first learn with the Golden Beads work. Here is a great example of that lesson. The works continue through gradual levels of abstraction until all that is needed is pencil and paper. However, the student will have the benefit of knowing why things are done a certain way. I always did well in math when i was in school, but i learned abstractly like most students in traditional schools do, learning that you carry the one, because you carry the one. When i went through Montessori teacher training, and learned how to do things like long division and binomial cubing with concrete materials (all of which is done in grades 1-3 in Montessori by the way) i had some major breakthroughs in understanding!
Isolation of variables
Each Montessori material focuses on only one concept at a time. For example, the pink tower (seen here) is made up of blocks that are all the same color and same shape. They vary in their dimensions only. This so different from typical educational toys, flashcards, worksheets, you see elsewhere. For example, my girls have a shape sorting toy with a red circle, blue star, yellow triangle, and green oval. If i were to pick up one of the shapes and say, "this is green," how are they supposed to know if i'm talking about its color or its shape? This seems like a pretty simple and obvious idea for education, but i bet you'll start noticing now how frequently it is disregarded.
Practical life skills
Did you know that 3 year olds can safely and skillfully peel and cut carrots? They can! The so-called practical life works are a hallmark of Montessori education, though they are seen more in the 3-6 classroom than later on. Children of this age have lessons on and spend time doing things like silver polishing, carrot peeling, blowing noses, folding clothes, buttoning/zipping/tying clothes, setting the table, dusting, sweeping, and sewing. Anyone who has spent time with a small child knows how eager they are to participate in everyday activities, hence the plethora of garish plastic toys which emulate such. Montessori curriculum takes that desire of the child to engage in useful work seriously, and eliminates the obstacles by pairing tools and furniture which are of the appropriate scale (think little brooms, chairs, stools, etc.) with lessons which are given at the appropriate time. It is amazing what little ones are capable of when those two stars align!
Mastery of skills
In traditional education, the students all learn the same thing at the same time. Later they are all tested on the same thing at the same time. A grade is given. Then everyone moves on to the next thing. If you understood the target concept early on, then you would pass the time in boredom until the next level. If you still did not understand the target concept at testing time, you would be even more behind at the next level. This sad tale is not told in Montessori education, where each child progresses at their own pace and does not move on from a work until they have mastered it, or conversely, moves on to the next work as soon as they have. The point is for the student to obtain understanding, not for teachers to have a number they can enter in the gradebook on the arbitrarily determined testing day.
Holistic education
The education that takes place in subjects like math, language, and biology is phenomenal. But that's not all children learn in Montessori schools. Children also receive conflict resolution lessons and learn to live in a community. There is great emphasis given to the care of nature. Most Montessori schools have a garden, and every classroom has at least a few plants that the little ones can water. Students are responsible for classroom pets, and some schools even have goats or chickens! Finally, Maria Montessori dreamed of her new approach to learning to be means of developing world peace. If children are allowed to follow the natural course and drive to learn, unhindered by the mechanistic approach of traditional learning, imagine the sort of adult they will become. All of this has been part of the philosophy for 100 years-long before being green and celebrating diversity came in vogue :)
There, in a nutshell, are my (hopefully coherent) points about what the Montessori philosophy is all about. For some lovely quotes by Maria herself (yes, we are on a first name basis), go here.
I'd love to hear what prior conceptions of Montessori other have had. Or, if you're already familiar with Montessori, what has your impression or experience been like?