FREE for a limited time – Arithmetic Invaders: Grade 3 Math Facts. Kids defend the planets from invaders in this math game. The table of contents shows the titles of the missions, a short description of the math required, and the high score for that mission. There are 8 “missions” to complete – 2 addition, 2 subtraction, 2 multiplication, and 2 division. With completion of the last mission, your child earns the highest rank – DEFENDER OF THE SOLAR SYSTEM. In each mission, the child matches the value on the laser gun to an equation having the same value – written below 1 of 3 invader ships. The mission’s length can be 2, 3, or 5 minutes. Even though the title implies that the app only practices facts, the addition & subtraction missions include 2 digit numbers. All in all, this educational app provides another fun way for kids to practice math!