This "letter to teachers" suggests reasons teachers should be interested in research findings. Research findings in several areas are summarized and interpreted so that they are useful to teachers of elementary school mathematics. Among the areas that are highlighted are: (1) time allocation; (2) low achievement; (3) active teaching; (4) use of materials; (5) calculating and computing; (6) broadening the curriculum; (7) communicating about mathematics; (8) using what children know; (9) learning from each other; and (10) providing equal access. (PK)