Because second grade students had difficulty in explaining what they knew about the number 15, it was suspected that they did not understand place value. Realizing every number has a place value and its place provides facility for calculation, a teacher attempted to ascertain second grade students' (N=18) knowledge of place value. Results of individual interviews indicate that 72 percent of these students did not understand the meaning of place value, although they understood counting by ones. Since much time is spent teaching place value in the first grade, students in grades 1 (N=40), 2 (N=18), 3 (N=18), and 4 (N=18) were also interviewed to determine when children do learn place value. Results indicate that students show an understanding of place value in grade 4 whereas, even though it is taught in earlier grades, there appears to be little or no understanding. Therefore, it is recommended that teachers need to spend more time in helping students develop the ability to think through the use of concrete materials. (JN)