Subtraction is a timed drill for kids learning their subtraction facts. Students click numbers to solve equations. Adjust the level for harder problems or word-based subtraction. Children who need help can observe the dog jumping the number line to calculate the right answer. This app makes subtraction fun. Kids try for better scores, requiring quicker, more accurate answers.

The user experience is so simple that children know intuitively what to do: enter your name, click Go and click the right answers. The game is designed for children who have a basic understanding of how to subtract numbers. No other reading skills are needed. Subtraction's large numbers and buttons are accessible by kids with physical movement challenges. High scores are saved per student, so everyone competes against his or her own previous score, not someone else's.

In the info screen, accessible by clicking the blue info button, teachers can turn on negative numbers for students studying the subtraction of negative numbers.

Please note, the dog eventually shows students the correct answer for each question if the student understands how number lines work. This is intentional. However, the student will only be able to beat previous high scores by answering more quickly than the dog can jump. Once the student knows the math facts, the dog becomes irrelevant.