Is it permissible to take money in exchange for teaching students to memorize the Qur'an during the summer, given that their attendance is irregular?

It is permissible to take a wage for teaching the Qur’an. This wage becomes due upon enabling the utilization of the benefit. Therefore, there is no objection to taking the allocated amount even if the students do not attend, because a private employee is entitled to the wage if he makes himself available and the employer does not utilize him. Thus, the wage becomes due upon the passage of the time period, or upon enabling the employer to benefit.