Such short-term missions teams come under fire for being a waste of money, better spent on people in need and not a flight, 'flash in the pan' ministry that has no bearing on long term change in a given area, and largely about the young person or child having a great experience. While these criticisms are understandable, they are also perhaps based on misunderstanding, and done well, the fruit, influence and impact of such trips can be vast and significant.
Firstly, it is true that it will be significant for the young person on the trip. For them, there is a significant discipleship element to the trip. They will encounter God's love for others in a new way and they will perhaps be forced to rely on God in a way they never have before. Not only that, but when under pressure in a new, sometimes uncomfortable place, with a team of people, your character is put under a magnifying glass and a whole lot of ugly is exposed some of which you can't ignore!
As Tim Ghali writes regarding training young people to be missional, outwardly and kingdom focused, it is important to see the needs of others. Spending time doing that with other young Christians in the context of worship, prayer and seeing God's broken heart for those in need is a good way to do it, in the same way that a camp or a festival may be a deep, life changing experience, worshiping with others.
"...if you want to convince a student to become less self-absorbed, you need to show them the physical/ emotional/ spiritual poverty of others."