Table 1.

Location and corresponding IDs.

Place	Dean's office	Teachers' office	Science classroom	Canteen	Reception room	Class 1, grade 1
Corresponding ID	1487	1540	1574	1398	1363	1538
Place	Class 2, grade 1	Class 1, grade 2	Class 2, grade 2	Class 1, grade 3	Class 2, grade 3	Class 1, grade 4
Corresponding ID	1534	1405	1537	1456	1576	1558
Place	Class 2, grade 4	Class 1, grade 5	Class 2, grade 5	Class 1, grade 6	Class 2, grade 6
Corresponding ID	1564	1543	1514	1479	1365