\input zb-basic \input zb-matheduc \iteman{ZMATH 2014d.00544} \itemau{Poon, Kin-Keung; Man, Yiu-Kwong} \itemti{Dynamic learning approach to studying curve stitching on a unit circle.} \itemso{Teach. Math. Appl. 32, No. 4, 223-229 (2013).} \itemab Summary: In this article, we report a study on how students learn elementary number theory concepts via pre-constructed activities of curve stitching on a unit circle. By using a dynamic learning approach, students were able to observe and guess the patterns of curve-stitching figures and explore how they were related to the total number of points on the circle and the interval between any pair of connected points. The subjects were pre-service and in-service primary mathematics teachers majored in mathematics or information technology in a BEd programme offered by the Hong Kong Institute of Education. We also discuss some teaching and learning issues related to this topic. \itemrv{~} \itemcc{F65 K35 G95 D85} \itemut{curve stitching; teaching activities; dynamic geometry software; elementary number theory; greatest common divisor} \itemli{doi:10.1093/teamat/hrt017} \end