Media headlines often announce that U.S. students do not shine in international comparisons in mathematics and science, but seldom does any one focus on the specifics of how instruction differs among countries and how U.S. educators can alter their practices to improve student achievement. Examining key findings from the Third International Mathematics and Science Study (TIMSS) 1999 Video Study provides important insights into ways to improve teaching and increase learning in mathematics and science. The study collected videotapes of eighth-grade mathematics and science lessons in the United States and in countries that outperformed the United States on the TIMSS assessments. A random sample of 100 science lessons and 50-140 mathematics lessons was videotaped in each country across a school year. The video study examined: (1) Mathematics teaching practices in the United States and five countries (Australia, the Czech Republic, Japan, the Netherlands, and Switzerland) and Hong Kong, which achieved higher scores than the United States; and (2) Science teaching practices in the United States and four higher-achieving countries (Australia, the Czech Republic, Japan, and the Netherlands). The study provided detailed pictures of typical mathematics and science teaching practices. The results suggest ways to improve mathematics and science teaching in U.S. schools--especially how problems are presented in mathematics lessons and the role content plays in science lessons. (Contains 4 figures.)