Michelle Obama now holds part of a world record. The first lady announced in an email Monday that her October bid to break the record for the most people doing jumping jacks in a 24-hour period succeeded. Mrs. Obama says 300,265 people participated, shattering the old record. In order to achieve her goal, Mrs. Obama led about 400 elementary and middle-school students from Washington in jumping jacks on the South Lawn of the White House. Other jumping jacks events were held around the world on Oct. 11.