A funeral was held today in Waterford, Wisconsin for 16-year-old John Tomlin, a student who was killed in last week's attack on Columbine High School in Littleton, Colorado. Meanwhile, investigators continue to examine the possibility that the two shooters had help in planning or even conducting the attack. Three boys who were found lying in the grass outside the school on the day of the incident have been re-questioned, but are not considered suspects. And Denver is appealing to the National Rifle Association to cancel its convention, scheduled to take place this weekend in Denver. NPR's Eric Westervelt reports.