What you are doing of sponsoring a number of poor families is a good deed for which you are to be thanked, and we ask Allah to accept it from you.
What people give of charity is of two types:
Obligatory charity, namely zakaah. It is not permissible to give this to anyone except those whom Allah mentioned in the verse (interpretation of the meaning):
“As-Sadaqaat (here it means Zakaah) are only for the Fuqaraa’ (poor), and Al‑Masaakeen (the poor) and those employed to collect (the funds); and to attract the hearts of those who have been inclined (towards Islam); and to free the captives; and for those in debt; and for Allaah’s Cause (i.e. for Mujaahidoon — those fighting in a holy battle), and for the wayfarer (a traveller who is cut off from everything); a duty imposed by Allaah. And Allaah is All-Knower, All-Wise”
It is not permissible to give zakaah to one who is able to work and earn enough to suffice him, because the Prophet (blessings and peace of Allah be upon him) said: “There is no share of it [zakaah] for the one who is independent of means or one who is strong and able to earn a living.”
Narrated by Abu Dawood, 1633; classed as saheeh by al-Albaani in Irwa’ al-Ghaleel, 876.
Mustahabb charity, which is what a person gives other than zakaah. It is permissible to give this to both poor and rich, but it is better to give it to the one who is in need of it.
Al-Nawawi (may Allah have mercy on him) said: It is permissible to give voluntary charity to the rich, and there is no difference of scholarly opinion on this point. It is permissible to give it to them and the giver will be rewarded for it, but it is better to give it to the needy. Our companions said: It is better for the rich person to refrain from taking it and he should not ask for it, and it is not permissible for the rich person to accept voluntary charity, making a show of being poor. End quote.
For more information please see the answer to question number 82673.
Based on that, if the money that you are giving to those families is zakaah money, it is not permissible to give it to them, except those who are poor and not able to earn a living.
If the money that you are giving to them is mustahabb charity, then it is permissible for you to give it to them, although it is better to give mustahabb charity to one who is poor, so as to meet his needs.
You will not be sinning if you do not give this money to those who are able to earn a living, because they are not in need of it.
If the givers of the money stipulate that their charity is only to be given to the poor, in this case you will have to give it to the poor only, and it is not permissible for you to give it to someone who is independent of means.
You should advise those who are able to earn a living to stop asking of people and to do work from which they can earn money that will spare them from having to ask of people.
And Allah knows best.