★ ★ ★ ★ ★ Subtraction - Math 1st grade * This is the useful application with lessons designed scientifically and suitable for 1st grade kids. * Lessons are illustrated with lively sounds as well as images to enhance kids’ concentration. * Lessons are classified according to topics and arranged from the easiest to hardest so it’s convenient for kids to study. * Lessons are shown as a play so it raises kids’ inspiration more than worksheet. * Lovely and simple interface helps kids to easily study by themselves.