Raising kids isn't easy — and the theories behind it are, inevitably, controversial. In 2010, many aspects of parenting were called into question, from disciplinary strategies to expressions of affection. Here's a quick look at the seven most-heated parenting debates of the year:

1. Should circumcision be banned?
A parent's right to circumcise his or her sons has long been disputed and, now, a San Francisco man believes he's found a way to end the battle. Lloyd Schofield is gathering petitions to force a citywide referendum on whether it should be illegal to "circumcise, excise, cut, or mutilate the foreskin, testicle, or penis of another person who has not attained the age of 18." Read more about his initiative.

2. Why is ADHD on the rise? 
Nearly 10 percent of American children have been diagnosed with attention deficit hyperactivity disorder (ADHD), according to a report released this year. That's a shocking 22 percent jump since 2003. There is no shortage of explanations. Was it something we ate? Have doctors' diagnostic powers improved? Or are parents just more paranoid? Find out more.

3. Does writing by hand makes kids smarter?
Kids do so much typing and texting these days that many get little practice with their handwriting. Unfortunately, it's not just their penmanship that suffers. It turns out children who rarely write with pens and pencils are missing out on an activity that is crucial to brain development and the honing of fine motor skills. Check out one of The Week's most read stories of 2010.

4. Is kissing your kid on the lips creepy?
A peck on the cheek is universally accepted as a tender expression of a parent's love for his child. But a smooch on the lips? Parenting bloggers clashed on this question; while some find nothing wrong with it, others insist that kissing kids on the lips can become a little creepy once a child is no longer a toddler. Find out more.

5. Do daughters cause divorces?
Statistics show that parents with daughters are less likely to stay married than those with sons. Do daughters drive their parents apart? Do women with daughters need their husbands less? Or is it "dehumanizing" to even look for generalizations that explain something as complicated as divorce? Click here for the full story.

6. What is behind the early puberty epidemic?
A study published in the journal Pediatrics found that girls are hitting puberty earlier than ever. Fifteen percent show signs of breast development by age 7 — that's twice as many girls as a decade ago. Is rising obesity to blame, or might the shift be linked to hormones and chemicals pumped into our food? Read more.

7. Will spanking make your child successful?
Corporal punishment is always a hot topic. But a recent study by a Calvin College psychology professor suggests that adults who were consistently disciplined with calm, deliberate spankings up to age 6 enjoy higher levels of success and happiness than their peers who were spared the rod. Advocates of firm discipline said the findings vindicated them. The "anti-spanking crowd," of course, had a different interpretation. Get the full debate.