I was relieved today to read Let’s Not And Say We Did at Right Wing Nation (no, I'm not a regular reader of that. I came to it through a post at Kitchen Table Math).
It's good stuff. Three commonly cited reasons for teaching Latin are laid out and then addressed. The reasons are:
Studying Latin teaches students grammar.
Studying Latin teaches students Latin roots.
Latin histories are part of our culture and history.
The author mostly seems to address the first question but he does so well, arguing that if helping kids to understand english grammar was a concern then we'd do better teaching them German. I'll let you read the original post and decide whether you agree or not.