At this time, school was ongoing and the students were already in the middle of classes.
The Elementary tier had various classes, some of which had to be further divided according to the results of diagnostic tests. These were exams that all students had to take at the start of the school year so the educators could have a better grasp of the student's level.
This was, of course, to maximize the kid's potential. This was also to give time and chance to the children new to the various concepts to adjust accordingly.
This was especially applicable to the aborigine kids who comprised the majority of the students.
For instance, there was Xeno language literacy and math class which was too alien to the aborigine children and had to be taught in the nursery level.
In the meantime, all Terran elementary school students like Maya, Mimi, and Horus were taking the 'proficient class'.