Everything Balances Out in the End

Students use a pan balance to study equality, order of operations, numerical and variable expressions, and other key algebraic concepts. In this three lesson unit plan, equivalent relationships will be recognized when the pans balance, demonstrating the properties of equality. Students also use this pan balance (numbers) applet to practice the order of operations in simplifying numerical expressions and to demonstrate the conventions of using algebraic logic in simplifying expressions. Lastly, using the same tools, students determine if algebraic expressions are equal.

Standards & Objectives

Learning objectives: 

Learning Objectives:

Students will:

  • Complete a chart by doubling or halving numbers.
  • Compare data by use of vertical and horizontal bar graphs.
Essential and guiding questions: 

Questions for Students:

  • When would you need to halve a number?
  • Provide an example of when you would need to double a number.
  • Assume that Amy's parents told her she weight 6 lbs. at birth. How much did she weight six months later?

Lesson Variations

Blooms taxonomy level: 
Extension suggestions: 


  • Students can order the students' weight at birth from least to greatest.
  • Students can find out (from their parents) their birth weights and weight at six months to determine if these weights follow the rule of thumb as discussed in class.

Helpful Hints


  • Two colored crayons for each student (preferably red and brown)  
  • Baby Weight Activity Sheet 
  • Grid Paper