Maricopa County keeps growing, but school-age kids are a shrinking part of it

Maricopa County has more school-age kids than it did in 2006, by the Census Bureau's estimates. It just hasn't added them anywhere near as fast as it has added everyone else. Lately, the count of kids has slipped.

In 2006, school-age children made up 18.8% of the people the Census Bureau counts in Maricopa County for its local poverty estimates. By 2024 that share had fallen to 16.2%, a drop of 2.6 percentage points, according to the bureau's Small Area Income and Poverty Estimates.

Children still make up nearly 1 in 6 people in that count. But the share has slid, and it comes from a gap in growth, not from children disappearing.

From 2006 to 2024, the school-age count grew 6.5%. Over the same years, the all-ages count grew 23.6%.

• School-age children, 2006: 698,432
• School-age children, 2024: 744,159
• All ages, 2006: 3,719,845
• All ages, 2024: 4,598,031

Spread out year by year, the number of children grew about 0.4% annually. The whole population in the count grew about 1.2% annually. Stretched from 2006 to 2024, a small yearly gap like that adds up.

Kids down, county up since 2020

Recent years have widened the gap. From 2020 to 2024, the count of school-age children in Maricopa County fell 2.8%, while the all-ages count rose 2%.

So Maricopa County's school-age count ends this stretch bigger than it was in 2006 but smaller than it was in 2020, even as the county's overall count grew over the full period and the recent one.

A specific count, not a head count

These figures are not the bureau's official population estimates (St. Louis Fed). For counties, the bureau builds them with a model that combines survey data with population estimates and administrative records (census.gov). They are not direct counts from a census or from records, and not direct results from a survey (census.gov).

Some people are left out of the count. Residents of college dormitories, military housing and all institutions are excluded (St. Louis Fed), as are certain children who aren't related to the household's reference person by birth, marriage or adoption, such as foster children (St. Louis Fed). That makes the child share a share of this particular population, not of every person living in the county.

Why begin in 2006? The bureau's definition of this population has been the same since then and matches the one used by the American Community Survey (St. Louis Fed). Earlier figures came from a different survey, which marks a break in the series (St. Louis Fed).

Where federal school money follows the count

None of this is an academic exercise. The program's main purpose is to supply income and poverty estimates for running federal programs and dividing federal funds among local jurisdictions (census.gov). The bureau also produces estimates for school districts to carry out Title I of the Elementary and Secondary Education Act (census.gov).

For parents and school boards in Maricopa County, that means the shrinking school-age share isn't only a line on a chart. It is part of the estimates the federal government uses when it divides money among local jurisdictions.

About the data

We used the Census Bureau's Small Area Income and Poverty Estimates for Maricopa County, comparing the number of school-age people in the poverty universe with the all-ages poverty universe from 2006 through 2024. We calculated the school-age share for each year, total and compound annual growth for both groups, and the change from 2020 to 2024. The comparison begins in 2006, the first year of the current poverty-universe definition.

• These are model-based estimates, not direct counts, so small year-to-year changes may not be meaningful.
• The poverty universe excludes people in college dorms, military housing and institutions, and some unrelated children such as foster kids, so it is not the county's full population.
• The figures cover Maricopa County only and show how the counts changed; they do not separate out the role of births, moves or other factors.

SAIPE: the Census Bureau's Small Area Income and Poverty Estimates program, which produces modeled income and poverty figures for states, counties and school districts. Poverty universe: the group of people for whom the Census Bureau can determine poverty status, which leaves out some groups such as institutional residents and certain unrelated children. Compound annual growth rate: the steady yearly growth rate that would carry a number from its starting value to its ending value.

Sources

• Federal Reserve Bank of St. Louis (FRED): Poverty Universe, Age 5-17 related for Maricopa County, AZ, latest period 2024, released Feb. 9, 2026; retrieved Oct. 21, 2026. Data
• Federal Reserve Bank of St. Louis (FRED): Poverty Universe, All Ages for Maricopa County, AZ, latest period 2024, released Feb. 9, 2026; retrieved Oct. 21, 2026. Data