Kimberly Payton, a teacher at the Small Savers Child Development Center, reads to a group of preschoolers in Washington, D.C., in 2010. Researchers say that teachers who make small changes in how they read to 4-year-olds can improve kids' reading skills later on. Ricky Carioti/The Washington Post/Getty Images hide caption

itoggle caption Ricky Carioti/The Washington Post/Getty Images

Four major universities are joining forces with Coursera, a Silicon Valley startup, to offer free online classes in more than three-dozen subjects. iStockphoto.com hide caption

itoggle caption iStockphoto.com

President Obama appeared with sixth-grader Keiry Herrera of Graham Road Elementary School in Falls Church, Va., as he spoke about No Child Left Behind last September at the White House. Charles Dharapak/AP hide caption

itoggle caption Charles Dharapak/AP