A:
Correspondence among boys and girls is unlawful. (Part No. 15; Page No. 85) This is one of the means that leads to immorality, perversion and committing unlawful deeds. If the reality is as you have mentioned, it is not permissible for you to help them or facilitate the exchange of their letters. In fact, your duty is to prevent it and advise those who exchange such letters as Allah (Exalted be He) says:
...but do not help one another in sin and transgression. And fear Allâh. Verily, Allâh is Severe in punishment.
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.