Welcome to Spring Fever" week in primary schools across the Netherlands, the week of focused sex ed classes. In the Netherlands, the approach, known as "comprehensive sex education," starts as early as age 4. You'll never hear an explicit reference to sex in a kindergarten class. In fact, the term for what's being taught here is sexuality education rather than sex education. All primary school students in the Netherlands must receive some form of sexuality education. The system allows for flexibility in how it's taught. But it must address certain core principles - among them, sexual diversity and sexual assertiveness. That means encouraging respect for all sexual preferences and helping students develop skills to protect against sexual coercion, intimidation and abuse. The underlying principle is straightforward: Sexual development is a normal process that all young people experience, and they have the right to frank, trustworthy information on the subject. "There were societal concerns that sexualization in the media could be having a negative impact on kids," [health promotion official Robert] van der Vlugt said. "We wanted to show that sexuality also has to do with respect, intimacy, and safety." The Dutch approach to sex ed has garnered international attention, largely because the Netherlands boasts some of the best outcomes. The teen pregnancy rate in the Netherlands is one of the lowest in the world, five times lower than the U.S. Rates of HIV infection and sexually transmitted diseases are also low.