Here in Uruguay homeless people are sadly, pretty common. Even if there are some social homes for them to pass the nighe, people hate go to there becuase these places are full of problems.
My mother taught me to help others, not with money if is possible, but if they ask for something to eat, give them some bread, fruits, rice, etc.
I remember one time, during winter. I was going to school and there was this gut searching things in the trashcan. We asked if we can help him with something and he said he was hungry, so we gave him $100 uruguayan pesos (more or less 4 dollars). Later he come to thanks us and showed us what he had bought, We talk with him and convinced him to go and try to talk with his family and ask for help.