Mar 04, 2012 - Montessorium announces in celebration of the 500th anniversary of cartographer Gerardus Mercator's birth, Montessorium is lowering the price of its educational app Intro to Geography: North America. For a limited time. This is part of a series including; Intro to Letters, Intro to Math, Intro to Geography: North America, and Alpha Writer. Montessorium's applications have received praise for their elegant design and education value. They have been showcased in national Apple commercials & more.