What is the expiation for not explaining the lesson on puberty in the religion class for eighth grade last year, and is it obligatory to explain it this year in a mixed-gender class given the teacher's embarrassment?

Teaching adult boys in co-educational schools is permissible if the female teacher adheres to hijab, and there is no private seclusion (khalwa) or soft speech. However, it is preferable to avoid it due to the inherent risk. As for abandoning lessons due to shyness, this is a mistake, and it was possible to request an arrangement to resolve the issue. The administration must be informed of what happened and forgiveness sought. Regarding this current year, the teacher must inform the administration of the problem. If they refuse (to address it), she has two options: abandon the lessons while informing the administration, or teach them while attempting to avoid words that cause embarrassment, and expel any student who makes suspicious movements. In general, it is advisable to refrain from teaching in co-educational schools, but if it is unavoidable, then she should teach the introductory grades. Governments must separate educational facilities for boys from those for girls.