The below article (from the New York Times) makes a great case for the importance of cursive writing. The author confirms much of what Montessori already knew!: to write before reading is more beneficial, writing in cursive helps minimize reversals and inversions of letters, writing helps with retention and memory, and writing fosters greater creativity!
Maria Montessori’s brilliant materials such as the sandpaper letters and the moveable alphabet are the first steps to a child’s learning to write. The sandpaper letters allow the child to practice the movement of writing in a very sensorial way: visually, kinesthetically, and auditorally. The moveable alphabet allows the child to begin “writing” before their hands are fully developed to form letters. The child has much practice with developing his hand muscles through a variety of materials and works in the classroom. After much practice with these materials, the child is able to form letters and words as she already has a great understanding of the letter/sound relationship–quickly a young reader emerges as well!
Check out the article to learn more about some of the research around handwriting: