Lesson objective: Practice measuring weight using a balance scale.

This lesson helps to build procedural skills with using a balance to compare weight. A balance is used here because it is a measurement tool which students will be asked to use to make comparisons. This work develops students' understanding that objects can be compared based on an attribute they share.

Students engage in Mathematical Practice 5 (Use appropriate tools strategically) as they learn and practice the procedure of using a balance scale to compare two objects.

**Key vocabulary:**

- balance
- heavier
- lighter
- measurement
- scale
- weight

**Special materials needed:**

- pan balance