Yes, this is alarming, and it does not bode well for our future. The Bible tells us about a time in ancient Israel when "everyone did as he saw fit" - and the result was social and moral chaos (Judges 17:6).
Why has this happened? I'm sure this has many causes, from the breakdown of our families to the blatant disregard of moral standards by some in the entertainment industry. I can't help but wonder if we are nearing the last days before Christ's return, when - the Bible says - "people will be lovers of themselves, lovers of money, boastful, proud, abusive, disobedient to their parents, ungrateful, unholy ... without self-control, brutal, not lovers of the good, treacherous, rash, conceited, lovers of pleasure rather than lovers of God" (2 Timothy 3:2-4).
But the basic reason is because we've forgotten God. When we leave Him out of our lives, we become our own rulers, and we want to live without any interference from Him. But in the end we only hurt ourselves.
Pray for our nation - and pray especially for your students. Perhaps you can't talk about Christ as openly as you wish you could, but you can challenge them to think about the way they are living, and by your life show them that there is another way - the way of Jesus Christ.