WASHINGTON ( CNN ) -- Eleven-year-old Carl Joseph Walker-Hoover liked football , basketball and playing video games with his little brother . Rep. Carolyn McCarthy says the effects of bullying are becoming more severe . But on April 6 , after enduring what his mother called `` relentless '' bullying at school , Carl hanged himself with an extension cord in the family 's Springfield , Massachusetts , home . `` What could make a child his age despair so much that he would take his own life ? That question haunts me to this day , and I will probably never know the answer , '' Sirdeaner Walker said in a House Education and Labor Committee hearing on school bullying . `` He had just started secondary school in September , and we had high hopes , '' she said . `` But I knew something was wrong , almost from the start . '' Watch Sirdeaner Walker describe finding her son 's body » . He did n't want to say at first , she said , but reluctantly told her of classmates who called him names , `` saying he acted gay and calling him faggot , '' Walker said . `` Hearing that , my heart just broke , '' she said . Rep. Carolyn McCarthy , D-New York , said the emotional and physical effects of bullying are becoming more severe and that the acts of bullying can continue outside school . According to the National Youth Violence Prevention Resource Center , about 30 percent of school-aged children in the United States are estimated to be involved in bullying , as either a bully or the target of a bully . Steve Riach , the founder of Heart of a Champion Foundation -- a nonprofit organization that says it offers educators an `` innovative and effective approach to developing character in the lives of their students '' -- said his organization has learned that students recognize that school safety can not be accomplished only with security guards and metal detectors . And students `` have told us that emotional safety is every bit a concern as physical safety , '' he said . Walker called school bullying a national crisis . `` I 've learned that bullying is not an inevitable part of growing up . It can be prevented , and there is n't a moment to lose , '' she said . `` We need a national solution to deal with it , '' she said .
House Education and Labor Committee holds hearing on school bullying . 11-year - old William Joseph Walker - Walker hanged himself April 14 . Boy had been subject to ` ` relentless '' bullying , mother said . One expert called bullying a national crisis .