Maria Montessori is much more complicated and interesting than the plaster saint her devoted followers have made her into,"" and Rita Kramer promises to tell it straight. Yet her biography leaves you with the sense that Dr. Montessori was indeed a saint--or at least a Mother Superior. She seems to have had no life outside her constant, zealous missionary operation to reform society through the proper education of small children, whereby we would achieve ""the eventual perfection of the human race."" Kramer relates an anecdote about a visitor who brought a bag of geometrically shaped cookies for the pupils of her original Casa del Bambini. The children, says Kramer, were so preoccupied with calling out the names of the shapes that no one thought to eat them. Apparently, they were as imbued with asceticism as their teacher. Montessori did have a son out of wedlock who became her most devoted disciple, although she never acknowledged their relationship publicly. By this very dry account, her life was all lecture tours, conferences, school openings, professional successes. She began as an educational pioneer, but became increasingly conservative and her star declined in her later years. Montessori seems to be a distinctly unexciting subject but neither has Kramer brought much imagination to her relentlessly compiled lackluster facts.