Why did Ana mulvoy ten leave in season 3 of house of Anubis?

Well, honey, Ana Mulvoy Ten left "House of Anubis" in season 3 because her character, Amber Millington, graduated from the boarding school. It's as simple as that - no drama, just the natural progression of a student moving on with their life. So, don't go looking for some scandal or juicy gossip behind her departure, sometimes things are just plain and boring like that.