I live among a Muslim minority and Islam is spreading here. Much effort is also being made by brothers to improve our Islam, and to invite and inform others. These efforts are being carried out by various registered organizations. Every organization is run by a committee. My question is whether Islam allows us to include females with the males in one committee and they sit together and discuss ways to benefit Islam. If not, then is it alright that the females discuss on their own and then inform the males of their decisions, etc.?

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

It is better that the meetings of men and women be held separately to discuss the matters of Da'wah and how to improve it. If one of the groups needs to know the activities of the other group it may be carried out through Maharim or in written material or the like.
However, there is no harm if there is any need to sit together provided the women are in complete Hijab, and avoid being soft in their speech or showing their beauty. Also, all the members should lower their gaze and the discussion should be limited only to the useful necessary matters.
Allah knows best.