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Lesson plan Grade 7 Math

Rivergate Utility's Retiring Operators: A Grade 7 Percent Lesson

A 50-minute grade 7 lesson using real workforce data and a fictional utility to practice percents of a workforce while surveying water-career education paths.

Objectives

  1. Students will calculate percents of a utility's workforce and of national operator jobs.
  2. Students will describe more than one education path into a water-sector career.

Vocabulary

Key words: operator, workforce, percent, median pay

Teacher overview

Water and wastewater systems are run by licensed operators, and a large share of them are close to retirement, which means many jobs will open soon. This lesson uses real national workforce figures alongside the fictional Rivergate Utility to practice percents of a workforce. It also asks students to name the different education paths into water careers, which range from a high school diploma with on-the-job training and a state license to certificate programs and to two-year, four-year, and graduate degrees. A common error is dividing by the wrong total when finding a turnover percent, so students should divide openings by the full number of jobs.

Procedure

Hook (5 min): Tell students that the people who keep drinking water safe are called operators, and that many are near retirement. Ask what might happen to a town if a lot of its operators retire at once. Record ideas, then introduce the fictional Rivergate Utility as the setting for the math.

Direct instruction (12 min): Share the national figures: about 10,000 operator openings are projected each year from 2025 to 2035, the country employed about 131,000 operators in 2025, EPA estimates that roughly one-third of the water sector workforce is eligible to retire in the next 10 years, and operators earned a median of $60,020 per year in May 2025. Note that the openings figure describes operators specifically, not the whole sector, and that all of the openings come from replacing workers who retire or move to other jobs, because total operator employment is projected to decline 6 percent over that period. Model one percent using different numbers than the handout, dividing openings by total jobs.

Guided practice (13 min): Walk students through what a workforce percent means using a small example, then discuss the range of education paths into the field, treating each as equally valid. Make clear that some operators start right after high school with a state license, while others enter through certificates or engineering and science degrees.

Independent practice (15 min): Students complete handout items 1 through 6 on their own or in pairs. Circulate and check that they divide by the correct total in items 2 and 4.

Closure and exit ticket (5 min): Each student writes one education path into a water career and one percent they calculated today on an index card. Collect and scan to confirm that most students can name a valid path and a correct percent.

Rivergate Utility's Retiring Operators: A Grade 7 Percent Lesson — Grade 7 Math
Name: ____________________________ Date: ______________

Student Handout

Use the fictional Rivergate Utility and the national figures given. In our scenario, Rivergate employs 40 operators.

  1. In our scenario, 30 percent of Rivergate's 40 operators are 55 or older. How many operators is that?
  2. If all of those older operators retire within ten years, what percent of the current 40-operator staff will need to be replaced?
  3. Nationally, about 10,000 operator openings are projected each year. About how many openings is that over 3 years?
  4. The country employed about 131,000 operators. If about 10,000 open each year, about what percent of all operator jobs turn over each year? Round to the nearest tenth.
  5. An operator earns the median pay of $60,020 per year and is offered a 5 percent raise. How many dollars is the raise?
  6. The retirement wave means many operators will be hired soon. List two different education paths a person could take into a water-sector career.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key

Answers below use the fictional Rivergate Utility and the cited national figures.

  1. Answer: 12 operators. 30 percent of 40 is 0.30 × 40 = 12 operators who are 55 or older.
  2. Answer: 30 percent. 12 of the 40 operators would need replacing: 12 ÷ 40 = 0.30, or 30 percent.
  3. Answer: 30,000 openings. At about 10,000 per year, three years is 10,000 × 3 = 30,000 openings.
  4. Answer: About 7.6 percent. Divide yearly openings by all jobs: 10,000 ÷ 131,000 = 0.0763, or about 7.6 percent turnover each year.
  5. Answer: $3,001. A 5 percent raise on $60,020 is 0.05 × 60,020 = $3,001.
  6. Answer: Accept any two valid paths, treated as equal. Examples: a high school diploma with on-the-job training and a state operator license; a certificate program; a two-year associate degree; a four-year civil or environmental engineering degree; or graduate study in hydrology or public health.

Differentiation

Support

Give students the division set up for items 2 and 4, such as "12 ÷ 40" and "10,000 ÷ 131,000," so they can focus on converting to a percent. Provide a short list of education paths for item 6 to choose from.

Extension

Ask students to find how many total operators Rivergate would need to hire over ten years if it replaces the 12 retiring operators and also grows its staff by 20 percent, and to explain each step.

ELL supports

Pre-teach "operator," "workforce," and "median pay" with simple visuals, such as a worker at a treatment plant and a middle value on a short list of salaries. Provide sentence frames for item 6: "One path is ___. Another path is ___."