Introduction to the pre-K-2 volume / Stephanie Z. Smith and Marvin E. Smith -- Using your own teaching as a site for research into practice / Mary Kay Archer, Theresa J. Grant, and Kate Kline -- Mathematical argument in a second grade class: generating and justifying generalized statements about odd and even numbers / Annie Keith -- Teacher as researcher: research as a partnership / Karen Schweitzer -- A look at a child's understanding of mathematical ideas through his representations / Ana Vaisenstein -- Using children's understandings of linear measurement to inform instruction / Linda Jaslow and Tanya Vik -- Classroom research informs Measure up: a different look at elementary mathematics / Claire Okazaki, Fay Zenigami, and Barbara Dougherty -- You changed my mind about triangles! / Laurie Renfro -- Using classroom assessment to support growth of number sense in first grade / Laurie Hands -- Uncovering children's thinking about pattern: teacher-researchers improving classroom practice / Regina Wicks and Rita Janes