What is the Islamic perspective on the variance in teaching quality between school lessons and private tutoring concerning effective explanation for students?

Question

Teachers have a duty to impart knowledge effectively, whether in school or private lessons, upholding their responsibility with integrity. It goes against trust and integrity when educators fail to explain adequately in school but excel in private sessions. This contradicts the principles of honesty and fairness outlined in Islamic teachings. As the Qur’an emphasizes: (O you who have believed, be persistently standing firm in justice, witnesses for Allah, even if it be against yourselves or parents and relatives) (4:135). Hence, teachers should strive for consistency and fairness in their teaching, ensuring diligent efforts in both settings without compromising their responsibilities, as exemplified in this Quranic guidance.