Humble ISD International Baccalaureate students are in Washington, D.C. at the International Baccalaureate Conference of the Americas. They are being honored for their "Out On A LIMB" walk-a-thon service-learning project that benefits Limbs International – nonprofit organization that provides artificial limbs for people in need. The International Baccalaureate conference includes more than 1,000 educators from North, Central and South America.