Can IB students ever skip classes?

ยง 26 SchUG talent promotion - skipping school levels

(1) A pupil who, due to his or her exceptional performance and talents, has the intellectual maturity to take part in the lessons of the next but one school level, is to be admitted to the next but one level of the respective school type upon request. Admission to the next but one school year is only permitted if there is no risk of excessive physical or mental demands. In case of doubt, the student has to undergo a placement test and, if necessary, a school psychological and (or) school medical examination. Primary school pupils may only be admitted to the next but one school year if the total duration of the primary school attendance is not less than three school years.

(2) In all performance-differentiated compulsory subjects, the pupil must be instructed according to the higher performance level and successful participation in the lesson according to the higher performance level must be expected in the next but one level.

(3) The school conference is responsible for the decision in accordance with Paragraph 1, and the departmental conference at schools with a departmental structure. Such skipping is permitted once in elementary school, after elementary school up to and including the 8th grade and after the 8th grade.

(4) If, after admission to the next but one school level (Paragraph 1), it turns out that the requirements for attending the school level in question are not met, the headmaster, with the consent of the pupil, must revoke his admission to the next but one school level and at the same time to announce his admission to the next school level. However, revocation or admission to the next school level is only permitted until the end of the calendar year of admission to the next but one school level.