Turning away from religion is the effect. The cause was increased access to science education, and the lessening influence of the hateful rhetoric of the uneducated previous generations.
Just as with the birth of the industrial age people are finding freedom to learn and educate. If it were up to fundamental christians we would still be in the dark ages. Teens are gaining access to scientific information that does not agree with the bronze and early iron age knowledge set in the bible. The effect is a higher education and advancement in the sciences not hindered by religious restrictions and dogma. People were burned at the stake for stating that the Earth was not the center of the universe, today we know for a fact that the Earth is not even the center of our solar system. Advancing in the sciences is the effect of teens leaving or turning their back on religion. Perhaps, some day, most of society will do the same.
Depending on if they were indoctrinated to "NEED" something outside themselves or if they were truly raised with as much freedom to question and use their own reason and critical thinking.
It SHOULD be the best thing for the human race. . . . To leave that which was steeped in so much myth and the supernatural and embrace the continuance and well being of the species as a whole, is a good thing.
Young people have seen the hypocrisy in religion and it has shaped them in many instances. Jesus showed us the way to worship properly. His example was the perfect one to follow. He also left a means for directing our lives and it is the bible. The bible is a very unique book, it has the ability to separate people by what they really our on the inside. It says at Heb 4:12 "For the word of God is alive and exerts power and is sharper than any two-edged sword and pierces even to joints from the marrow, and is able to discern thoughts and intentions of the heart"
This is why there are so many different responses to the bible. Sincerity, humility and deep desire to know your creator will always get you where you need to be.
The affects are truly sad, because they will never know all the wonderful things that God has for their future and all the help he has provide as they go through the difficult teen years. Ecclesiastes 12:,1,2
I can understand not wanting to be a part of the world of false religion, the bible speaks of the true religion and how they will worship the Father in spirit and truth. John 4:23,24
I believe it's not unusual for teens to question their religion sometimes rejecting and resenting the religion and everyone in it. If they're not pushed then as they mature they will remember what they've been taught. Some may change the way they want to worship but the core values they've learned, in most cases, will remain with them.