While kids are learning the three Rs in school, administrators are busy doing a math lesson of their own each fall.

Kids may learn to count in school, but the most important count to school districts is the changing totals of the kids themselves. It directly affects how much they receive in state aid and how much money they receive in local levies, which are imposed on a per-pupil basis.

According to preliminary data from the Minnesota Department of Education, the state enrollment figures remained relatively steady compared with 2011-12, decreasing from 839,426 students to 836,204 -- a drop of .38 percent.

But some individual districts experienced much greater change.

In the western suburbs, the Minnetonka School District saw the largest overall increase in enrollment, just over 4 percent. Janet Swiecichowski, executive director of communications for the district, attributes the growth to "outstanding educational options."

The 2012-13 kindergarten is the largest class in the history of the district. Swiecichowski credits the seven options offered -- full- and half-day kindergarten in both Spanish and Chinese language immersion as well as in English, plus a "Ready Start" kindergarten program especially for younger kids with summer birthdays. The district is finding that families are opting for an immersion program in increasing numbers -- 53 percent with this fall's kindergarten students.

"Minnetonka does not place caps on our enrollments in our specialty programs," she said, which has likely bolstered their enrollment. The language immersion program also continues to the middle school level, so it might pick up students from other districts who have aged out of their schools' programs.

Other specialty programs include recently revamped, rigorous academic opportunities in middle-school language arts and sciences and enriched fine arts opportunities at all grade levels, including music and theater.

At the other end of the spectrum is Eden Prairie, Bloomington and Hopkins, with a decline in enrollment of between 1 and 2 percent.

Minority enrollment

Despite the overall enrollment shrinking in some districts, minority population is growing across most districts. Eden Prairie, for example, saw its minority population grow 6.31 percent, to 30 percent of total students, even while its total enrollment declined.

With diversity increasing statewide at a rate 1.97 percent for 2012-13 over 2011-12, most districts in the metro area experienced increases in their minority enrollment, regardless of fluctuations in overall numbers.

The .38 percent drop in total enrollment statewide is paired with an increase in minority enrollment -- from 220,334 students to 224,672 who identified themselves as a minority.

In Burnsville, which saw a 6.23 percent increase in minority students, spokesperson Ruth Dunn noted that the district has been "gradually becoming much more diverse in the past 10 years."

Dunn said the Burnsville district now educates students who speak 57 different languages at home, with the three largest being English, Spanish and Somali.

Enrollment change elsewhere

In other districts, Brooklyn Center saw one of the larger enrollment growths -- a 4.3 percent increase. To keep up with demand, Superintendent Keith Lester noted that the district hired two new elementary school teachers and closed open enrollment in July.

He credits the increase in part to the McKnight Grant for literacy, which provides a million dollars a year for three years to pre-K through third graders, with training available for parents as well.

"People are seeing the program and saying 'wow'," said Lester. Though the enrollment increases were primarily at the elementary level, a teen parent program and soon-to-open childcare center attracted 10 to 12 young mothers to the high school.

The opposite has been happening at the state's largest school district, Anoka-Hennepin. According to preliminary reports, they experienced a 5 percent decrease in enrollment over 2011-12. The decline wasn't a surprise.

"We projected a continual, slow, steady decline as part of the decline in the birthrate," said spokesperson Mary Olson, who noted the district's enrollment peaked in 2004. Despite the change, Anoka-Hennepin schools hired nearly 200 new teachers and had no layoffs.

Sara Glassman • 612-673-7177