Designed by Montessori teachers and Award winning app developers, Montessori Math: Add & Subtract Large Numbers presents an in-depth, step-by-step approach to Addition and Subtraction, with Montessori material. This app makes the concepts of “exchanging” (carrying/borrowing) so obvious that even adults will be surprised. It also presents fundamental Montessori materials: the stamp game and the bead frame. Features: - Our exclusive Dynamic Progression Algorithm to follow each child’s progress individually. - 4 pre-determined levels. - Montessori color-coded place values to allow children to easily identify thousands, hundreds, tens and units. - 3 activities to learn addition and subtraction : the stamp game, the bead frame and the magic slate. - 3 games to practice operations: Missing Digits, Wiz Quiz and Bubble Game. - A number range from 0 to 9,999. - A “Monster lab” for added fun and motivation. - “Advanced settings” containing even more options. - A detailed "Note to parents" explaining the pedagogy behind each game. - 15 languages.