Rockville’s Thomas Naatz, a sixth grader at the Norwood School, and D.C.’s Matthew Wilson, a fifth grader at Blessed Sacrament, served the Washington area proudly on Tuesday in the preliminary round of the National Geographic Bee. Neither of the young men made it to the finals, but both finished strong among 54 competitors and wowed onlookers with knowledge of Yemen’s coastal Hadramaut region, cities near the Syriac mountains, Costa Rican presidents and obscure weathering processes. Finals will be held Wednesday morning at the National Geographic Society and broadcast on public television stations.