This is a good substitute app for when a child is absent from school (Montessori) for long periods or for when reinforcement is needed. However, the numbers I. The hundreds are read incorrectly. The number "643", for example, is read as "six hundred and forty-three". The correct way to say the number is "six hundred forty-three." In math "and" represents the decimal point as in "six and one tenth" for the number "6.1". This is troublesome because is error is repeated with each number in every section. I sincerely hope this will be fixed.