The Montessori approach to language is, at the beginning, a phonetic one, with children associating the phonetic sounds of the alphabet with their corresponding symbols (letters). Once children have established these sound/symbol relationships, they are able to explore the use of language as a means of communication and self expression.
The moveable alphabet (a large box filled with the letters of the alphabet) allows Primary-aged children to write before they have the ability to do so using a pencil and paper. Young children have a great capacity for language, and relish the opportunity to express themselves through their writing, whether they are making a list of their favorite animals or writing a simple story.
While working with the moveable alphabet, children write by sounding out the words. This results in creative, phonetic spelling. As teachers, we do not use these moments to correct the children's spelling, but rather use later lessons/presentations to teach the (many!) nuances of the English language.