Division of numbers by one math quiz. This is an interactive online math test on division. The particular skill involved is dividing by one. When dividing any number by one, the outcome is the same. With this rule in mind, kids are equipped to solve any similar problem. The worksheets section of this website contains related activities for more offline practice. Feel free to share. This division exercise is for kids in 3rd, 4th, 5th and 6th grade.