The objectives of this study centered on ability of first-grade students in seriate learning, the strategies used, the effects of the seriation variable on task performance, and the effects of the number of objects used. Students from four randomly selected schools were asked to order a set of 4, 6, 8, or 10 objects on length or weight. The sequence in which objects were placed in the row and the actual ranks of the objects in the final row was recorded. A 4 x 2 x 4 random block design was used. The Task Score (TS) was the Kendall Tau coefficient between the child's ranking of the object and the correct ranking. Three other scores were devised to distinguish strategies. Extreme Value Selecters (EVS) identified extent of value among unordered objects. Rearrangers (RAR) made an unordered row and then rearranged the objects until correct. Students in the Insertion Strategy group (INS) randomly selected an unordered object and inserted it in the ordered row. The most important finding was that successful performance on the seriation task was usually achieved with use of a relatively systematic strategy. It appeared that most of the students in the population had yet to master seriation with weight. (Author/EB)