UPDATED 08/01/11 11:08 a.m.

CHICAGO (CBS) — Summer vacation has come to an end for some schoolchildren in Chicago.

READ MORE: Chicago Weather: Warming Trend Continues, Rain Chances Persist

As CBS 2’s Kris Habermehl reports, most Chicago students will not be going back to school until Sept. 6. But charter schools are starting their new school years on Monday, for a longer school year and more time to impart the year’s curriculum.

A total of 13 schools, operated by the LEARN Charter School Network and the United Neighborhood Organization, started classes Monday.

At the Romano Butler Campus of the LEARN Network, 1132 S. Homan Ave., students will be in school through June 15 – reducing the traditional three-month summer vacation to a month and a half. Classes are in session from 8 a.m. to 4 p.m.

READ MORE: 3 Men Injured In River North Parking Garage Shooting, One Identified In Video As Rapper Lil Reese; Officer's Gun Also Accidentally Discharged

LISTEN: Newsradio 780’s Bernie Tafoya reports

LEARN says the longer school day means improved student success, with a 99 percent high school graduation rate and an 83 percent college enrollment rate.

The organization says students enrolled in charter schools from kindergarten through high school receive five additional years of education in total compared with publicly-operated schools.

On a related subject, Habermehl reminds motorists that students back in school means the return of school buses, crossing guards, students walking back and forth across streets, and school zones where the speed is cut to 20 mph on days when children are present.

MORE NEWS: At Least 31 People Wounded In Weekend Gun Violence In Chicago, 5 Killed

Furthermore, you may not use your cell phone if you are driving through a school zone.