Chicago Public Schools officials have been trying for years to boost attendance on the first day of school.

They've roped corporate sponsors into offering give-aways, moved the start of the school year past Labor Day, and held rallies to make sure parents get their kids into class pronto. 

This year's efforts, unveiled this morning at a press conference at Robeson High School on the South Side, featured a new twist: Twitter.

The district is relying on Facebook, Twitter and other social media to boost attendance, in addition to the usual strategies.

"The first day of school sets the tone for the entire year," said Mayor Richard M. Daley. "Any child who misses the first day is already behind."

CPS has an interest in attendance that goes beyond ensuring that kids get a full year of learning. Funding allocations are made based on school attendance, so schools that have a lot of kids playing hooky can see their budgets fall.

"When they're not there, that school is short-changed," said Daley.

As part of the social-networking campaign, CPS will enlist the help of celebrities and corporate sponsors to get the digital word out.

This year's sponsors include Target, which will offer discounts on school uniforms and some childrens apparel. Kmart will donate 1,000 book bags, and Office Depot will donate similar products. The Museum of Science and Industry wll give each student present on the first day of school a family day pass to the museum.

The city is also transforming the annual Bud Billiken Parade into an opportunity to encourage first-day attendance.

"That is basically a back-to-school parade," Daley said.