Futile Mission

QUESTION: Today's comes from GH...
"This summer, our church's youth group is going on a mission trip overseas for a couple of weeks. They'll be doing some construction work for a church there, but do trips like this honestly do any good? What can a bunch of unskilled teenagers do that the local people can't do for themselves?".

IRRELIGIOUS PERSPECTIVE:
In this question you don't mention anything about the destination country, so it can be assumed that it is a second or third world country. However, there are even missionaries who go to first world countries and it amazes me that they knock on my door to enquire if I have heard about Jesus Christ. Do they really think that I haven't? What a waste of time, money, and effort! No matter what level of wealth the destination country enjoys, the purpose of this trip is to convert people - that's what a mission is. Every culture has some sort of deity and/or belief system. I can't see the benefit that changing someone's deity will bring, all it will do is improve the stats for the missionaries. Changing the god someone worships will make no difference to their life.
Your youth group probably has the characteristics of most young people in that they are idealistic and full of energy, so even though they are light on experience, they have plenty to offer. As for helping with construction of churches in poorer countries it would be more beneficial if they helped in the construction of something useful such as wells or health clinics. When people build houses of worship the only benefit is to their religion, there is no benefit to the local populace because they undoubtedly already have a set of beliefs.

BILLY GRAHAM'S ANSWER:
http://www.billygraham.org/articlepage.asp?articleid=6131