Well the Christianity often practiced in the churches is not Christ like, but they volunteer for helping the poor, both in the west and abroad. The Catholic religion (if you call it Christianity), stopped and educated certain African tribes from killing twin babies, who were seen as demonic at the time. Of course there has been alot of atrocities committed that are adverse to Christ's teaching, to be holy, speak the truth of God, but turn the other cheek, do not give them reason to bad mouth God.

One could argue for many things. Universal education. Widely-available higher education. Widespread orphanages. Hospitals. Even Abolitionism. etc. etc. * But in my opinion, the greatest contribution (both direct and indirect) is the legal abolishment of pedophilia. Now: the origins of this go back to Judaism. We see the Biblical Old Testament condemning (heathen) temple child prostitution. (Yes: men would go to worship at a temple, and the act of worship would be to engage in sex with a boy or girl of their choice.) But historically the influence of pre-Christian Jewish morality didn't reach far beyond the borders of Judah and Israel. It wasn't until the Christian era, with the wide spread of Christianity throughout the Mediterranean and Europe, that we see pedophilia (include the ancient institution of child temple prostitution) being abolished by law. And with the Ages of Exploration and Colonization, European Christian-based moral opposition to pedophilia spread worldwide. *** Now of course one cannot say "Christianity has only done good, and great good, throughout history". But the question asked specifically for a contribution to society from Christianity, and IMO that is the most significant that is also indisputably attached to Christianity and the spread of Christianity. *** My number two pick would be Abolitionism, but the effects are far, far less widespread (surprisingly, most nations still have not outlawed slavery), much later in its influence, and some might dispute that it is (or more accurately: was) tied specifically to Christianity (though I find such arguments weak, Abolitionism was certainly originally and historically a Christian movement).

Christianity founded western society and culture by being the light of education and charity in the dark and middle ages after Rome fell.