Depending on what paper you read, kindergarteners either are or are not going to get explicit lessons about HIV in New York City.
Newsday reports that they are not, in fact, going ahead with lessons on how HIV is transmitted, though the New York Post's headlines might have you believe otherwise.
I don't teach kindergarten, but I've raised a kid, and I think five is way too young. Fourth grade? Maybe. Although I can't imagine how they'd find time between the standardized tests with which they bombard my nine-year-old daughter.