9. Donald Bren

Getty Images

9. Donald Bren

Real estate developer

2004-08 Giving* $908 million

Using property and wealth from his real estate business, Bren has given more than $1 billion, much of it to support education. Bren's commitment to schooling runs the gamut from students to principals to school districts to university scholars on his Irvine Ranch. This year Bren gave $8.5 million to THINK Together after-school programs, one of the largest private donations to after-school programs in California history. In 2007 gifts included $20 million for a new law school at University of California at Irvine and $3 million in annual grants, teacher recognition, and student scholarships. In 2006 he gave a $20 million gift to fund elementary fine arts, music, and science programs at schools in Irvine, Calif.

For more, visit the Donald Bren Foundation topic on Business Exchange.

*Based on public records and interviews with donors
Data: BusinessWeek, The Chronicle of Philanthropy and the Center on Philanthropy at Indiana University