Is it permissible to hold Islamic "festivals" (such as the Festival of Truthfulness or the Festival of Prayer) in schools, similar to other educational festivals, where specific days are dedicated to intensively explaining a particular Islamic principle?

Shaykh Muhammad ibn Salih al-Uthaymeen permitted the use of the word "festival" (مهرجان - mahrajan) for events held to energize and attract people, provided that such an event is not taken as an 'Eid (religious holiday) or held annually at the same time. However, it is preferable not to name Islamic events as "festivals" (مهرجان) to avoid imitating the holidays of the disbelievers, especially since the word "mahrajan" is the name of one of the holidays of the pagan Majus (Zoroastrians), and its celebration was abolished by Caliph Umar ibn Abd al-Aziz.