XLT (exalt) began in Atlanta, Georgia under the leadership of veteran youth minister Paul George. In many cities it is an event which draws from multiple parishes. It is really just the latest layer on the practice of Eucharistic Adoration which started, not in the Middle Ages as some would have you believe, but actually as early as the sixth century in Lugo, Spain, where the reserved sacrament was carried in procession and displayed on the alter.
Certainly Eucharistic Adoration received wide acceptance in the Universal Church in the Middle Ages. The monstrance appeared in the second half of the thirteenth century, before that the consecrated host was most commonly kept in a pyx.
The most important aspect of the celebration of XLT in a parish is that it does not replace the more conventional silent adoration, but supplements it. XLT draw teens and young adults into the presence of Christ. They should also be encouraged to spend time in silent adoration. In my opinion, the best way to do this is to arrange for a period of silent adoration during catechism.
It is common practice in many parishes to have adoration monthly. Sometimes this is nocturnal adoration, sometimes it is only from morning Mass until the evening. Most times there is a list to ensure that the Blessed Sacrament is never left alone while exposed. Often this list is filled by pensioners or others who have free days. Challenge teens to sign up for a block of time during the summer or after school.
Remind teens that often we spend time with friends partying; listening to music, dancing and talking. With really close friends we sometimes just sit silently. Being in each other's presence is enough. For adults and older teens this kind of quiet intimacy is most often practiced by loving couples, who often sit together for hours in silence.
Just so, it is possible to meet Christ in the charismatic experience of XLT and also find him in the quiet of silent Adoration. Neither venue is exclusionary.