AceShowbiz -

Some big stars have been pictured taking the stage of Wynn Hotel and Casino in Las Vegas over the weekend. Elton John, Jennifer Hudson, Jason Mraz, Peter Cincotti, Canadian Tenors, Bill Cosby and Rob Thomas came to the event that night.

Wearing floor-length purple gown, Hudson shared stage with David Foster in one set and was joined by AJ Green in another. Their performances were part of Andre Agassi Foundation for Education's 15th Grand Slam for Children benefit concert.

Held on Saturday night, October 9, the charity gig raised more than $8 million. Those who sat at the front rows during the gala event paid $8,500 each and behind them, there were people who paid from $1,000 to $4,000 for one seat. During his set, Rob Thomas jokingly addressed people at the front row as the "wealthy" and those sitting behind them as the "rich."

A kiss from Steffi Graf was worth $25,000, someone paid $75,000 for a vacation in India including lunch with Freida Pinto of "Slumdog Millionaire", $60,000 cheque was donated in return of swimming lessons from Michael Phelps, and many other donations. All proceeds went to Agassi's charities which include a public charter school for at-risk youth in Los Angeles.

"I am both impressed and thankful for the tremendous support we have gotten for this milestone, the 15th Grand Slam," Agassi said. "From the incredible group of artists who gave their time and talents, to the generosity of Genworth Financial and all of our supporters, this is a proud moment for us. The success of the event allows us to make a positive difference in students' lives as we work to transform education."