To say that nearly a decade of declining enrollment and five consecutive years of budget cuts have been a challenge for Nevada County's public schools and their administrators is putting it mildly.In 2000-01, there were 12,997 students enrolled in 50 schools in western Nevada County, according to the county Superintendent of Schools Office.But today, in the 2011-12 school year, just 11,050 students are enrolled countywide in 45 schools, representing a 15 percent reduction in enrollment in that span. And it appears the trend isn't changing anytime soon, school officials say."We haven't been presented any evidence that the declining enrollment will …