Am I still a Catholic?

My son has not been a "practicing" Catholic, but maintains he is still a member of the Catholic Church? In fact, he spends more of his time pursuing other Christian Religions than he does practicing the precepts of the Catholic Church. He still maintains he is a Catholic because he was baptized, received first holy communion, and confirmation. How does the Church view a non-practicing Catholic as opposed to a practicing Catholic?

Does it matter? Your son is a unique individual, just like every other person on this planet. Your son is capable of making his own decisions in life. If he wants to call himself Catholic while practicing Christianity, or if he wants to call himself Buddhist while worshiping Satan, that's his own decision. Let him be.