As the United States school population becomes more linguistically and culturally diverse, teachers are challenged to provide full access, equality of instruction, and appropriate learning environments to all students. It is estimated that more than 20 percent of the 45 million school-age children live in households in which languages other than English are spoken; 6 million are from Spanish speaking households. At the same time, only 12 percent of public school teachers and administrators are minorities and that number is expected to decrease; only 18 percent of elementary and 13 percent of secondary teachers have training to work with minority students with limited English proficiency. One key approach to improving the low achievement of linguistically and culturally diverse students is to emphasize training new teachers in strategies that focus on improving cognitive processes used in critical thinking, problem solving, and decision making. Also, teachers need to integrate students' language strengths in the teaching learning process, use standardized and authentic assessment information for better teaching and learning, and implement educational reforms in schools with low educational resources and many academically at-risk students. Knowledge of culturally diverse students will generate appropriate attitudes and school practices and instruction that addresses the culturally diverse students' developmental needs and learning styles. (Contains 26 references.) (ND)