The interviews were transcribed verbatim by the interviewer, and the transcripts were available to three other researchers to be reviewed without identifying information for data analysis purposes. The structures drawn on the iPad were transferred to a Word document and organized in a table. Some students only provided verbal responses and did not draw a specific 210 figure. The OC1 students were given the code names I1 to I6 (interviewees 1 to 6). The OC2 students were given the code names I7 to I12 (interviewees 7 to 12). This does not reflect the order in which the interviews were done.