Michelle Obama paused for a moment as she delivered her last scheduled public remarks as first lady in the East Room on Friday. Speaking during a ceremony to honor the 2017 school counselor of the year, Terri Tchorzynski of Battle Creek, Mich., she urged children to get the best education they can and then use what they learn to ‘‘lead by example with hope, never fear.’’ She also called her White House role “the greatest honor of my life.’’