Speak to him about pornography.  It is perfectly normal for a boy his age to be curious. Explain that you understand the nature of his curiosity, but also explain how porn degrades women, enslaves some, and is not how adult sexual behaviour is generally perceived or practiced. Anecdotal evidence suggests that pubertal boys will go on line for these sites once to three times a week dropping off interest in late high school.

Advise him about "Kidde porn" which is illegal in most states.  It is difficult for most people to tell who is under 18 in these secenarios; however many police units have watch dog sections checking out the net and who is chatting. Children are unaware they can be caught in a sting.

It is a useful topic for the local PTA to address at a meeting.  You are not the only parent who has found this an issue. Use your community strengths to be sure this is addressed and put filters on your computers to delte pop ups.

Wayne Yankus, MD, FAAP
expert panelist: pediatrics

His hormones are running wild and will continue to do so for a few more years. He needs to be told how this degrades women and how not only do the women become slaves but the viewer also becomes enslaved to porn.
 
This could effect his mature relationship in the future when there needs to be more than lust to have a fulfilling relationship.
He needs to know future goals, shared beliefs and a best friend would be better for marriage. Too many people fall into lust and think it is love. When the lust dies down they find they have nothing else in common.
 
Also there is the fear of becoming addicted to porn.
 
Does he really need to have access to the Internet with his cell phone? Schools have computers for students. Sometimes we try to feel good about being a parent by competing with other parents by giving too many unnecessary costly item.