What is the ruling on marking an absent female student present in attendance records, knowing that lecturers permit it, that absence saves her effort and time, and that her group's lectures are bad?

Lying is forbidden except out of necessity or need. Scholars have permitted lying that does not harm others if it achieves a benefit, and it becomes obligatory if the intended purpose is obligatory. If all the assigned lecturers for your group are bad and there is no benefit in attending their lectures, then there is no harm in attending with other lecturers in the manner mentioned, if no other means are available.