You guys must read a lot of Ayn Rand or something.
See, as an atheist, the only way I will 'live on' is by being remembered in the future, after my death. And only the best and the worst get remembered. I don't want to be remembered as a bad person, so I try and will continue to try to do good, and hope that someone will remember me, or at least keep my legacy and ideas alive. That is immortality. And that kind of immortality is much more meaningful than any afterlife.
So you see that is the reason to be a good person. While that maybe subjective in a certain way, but not overall. For example, people will remember Johann Gutenberg in a positive light. He changed the world, possibly more than anyone so far. On the other hand, Hitler will always be remembered as a bad person, one of the worst individuals the world has ever seen. Only very small minorities look upon Hitler positively.
While I will most likely never be among the ranks of Imhotep, Leo Da Vinci, Joey Gutenberg, Tommy Edison, or Billy Gates, I hopefull will find my niche in history. By the way, if you ever want to be inspired, read about those guy. Probably the most brilliant minds the world has ever seen.
As for religion being in schools, there is nothing wrong with talking about religion or God or spirituality, since it has been so very influential on humanity. However it is not appropriate to teach or preach and religion or spirituality. It is equally inappropriate to teach not believing in any deity. Looking at religion and spirituality, or lack thereof, in an objective way is the only appropriate way to address religion in publically funded schools. I'm sure you could imagine me not wanting my tax money going to teach any religion or spirituality.
Just imagine schools teaching kids to be atheists. That's how I feel about teaching anything other than proven facts, or at least theories. And religion and spirituality is no theory, but rather faith. Faith should never be taught, but rather experienced.