This is a complete instructional activity about the concept of divisibility and common divisibility rules. It briefly reviews the concepts of factor, divisor, and a number being divisible by another. Then, the "easy" divisibility rules...

This lesson plan presents the idea that the area of any triangle is exactly half of a certain parallelogram -- thus we get the familiar formula of multiplying the base and the altitude and taking half of that. The lesson plan contains...

This is a complete lesson with instruction and varied exercises about how to multiply a whole number by a decimal.

This lesson presents the idea that the area of any right triangle is exactly half of a certain rectangle, and contains varied exercises for learners.

This instructional activity contrasts area and perimeter and has varied exercises for young scholars about both concepts.