Because it was the first day of school -- and because she had experienced that very sensation that morning -- fourth-grade teacher Julie Tozer asked her students, "What does it mean if your hands get clammy?"

"Hard?" one of the students at Flora M. Singer Elementary School in Silver Spring ventured, before another student responded: "Slippery and soft and sweaty."

"Right, because that's what happens when you get nervous," Tozer said. "Were any of you nervous to come to school today?"

Resoundingly, her class said no.

If the first day of school should have been anxiety-inducing for any school, Flora Singer was it: New this year, the school still sported a sign warning nonconstruction vehicles to stay out of the parking lot. The $22.9 million, 95,831-square-foot campus is the latest expansion of the Montgomery County Public Schools system as it grapples with fast-increasing enrollment. More than 149,000 students were signed up for the first day of class, about 2,500 more than last year and 10,000 more than a decade ago. MCPS also ushered in the school year with a new, expanded campus for Paint Branch High School in Burtonsville.

But despite the strain, students, parents and staff across the county reported that all was in order for the first day of class. John Landesman's daughter, a seventh-grader at Eastern Middle, successfully picked out a first-day outfit, while a kindergartener at Flora Singer was excited to find a folded-up napkin in his lunch reading "Hope you have a great first day of school!" from his mother.

Superintendent Joshua Starr said the school system will continue to focus on closing the achievement gap between minority students and their white and Asian peers, while providing more interventions for struggling students and emphasizing critical-thinking skills.

"We were the first district in the country, in many ways, to go to the moon," Starr said. "Now we've got to figure out what it will take to get to Mars."

In Kensington, the county's first charter school, Crossway Community, began classes, as did Loudoun County Public Schools.

DC Public Schools and most of the city's 57 charter schools -- including three new schools, with a fourth new charter slated to open in September -- opened on Monday, unhassled by the chaos that marked school openings in years past. Whereas five years ago, textbooks and desks gone AWOL were the norm, parents and teachers across the city said the sailing was smooth.

DCPS is expected to announce school closings by the winter, as enrollment is just beginning to even out after falling steeply over the past four decades, leaving many buildings with vacant space. Many students have left for charter schools, which now claim 41 percent of the District's public school students. But even so, some DCPS schools saw early signs of growth.

In the Congress Heights neighborhood of Ward 8, M.C. Terrell/McGogney Elementary School drew 244 childen and is hoping to reach 250, far above last year's 207.

"We're usually all-black, but this year we have students who are Spanish-speaking, multiracial and white students," Principal Atasha James said. "It's really cool that we're diversifying, and despite the fact that a charter school opened up right across the street."