Okay, so I have really gotten into Ninja Turtles over the past 3 years. I might seem a little prejudiced, based on my love for them.
I think Ninja Turtles should be around 9 and up. Mainly I feel this way because the show gives details about certain things. There have been (To my remembrance) two deaths of characters. I do feel the mutations (Although look amazing and simply beautiful in the eyes of an animation lover) could be very violent or traumatic for children too young. Have you seen one of the mutations? There is often screaming and ripping sounds. It is a very violent series of events. If you can get past the uncomfortable sounds of screaming from mutations, there is also the violence. Obviously everyone has mentioned Ninja Turtle violence, but yes, the show does need it. It is a show about Ninjas after all. Sometimes the violence goes too far for younger children (Ie. The Good, The Bad, The Casey Jones, Raphael attacks Leo. Though not causing too much damage, it is still out of anger and violence) (Ie. The ending of Annihilation Earth, shows death, but no blood) The language of the show isn't too bad, but sometimes you catch a few things they used based off of cuss words (Ie. Episode The Creeping Doom, Mikey says, "Meet the Grass Kicker" Referencing the phrase A** Kicker) (Ie. In multiple episodes Mikey says things like "That's my ninjas." This is a reference to "That's my n*ggas.")
I have been mentioning the bad, but this show truly does have the heartfelt moments that I love. Sometimes the show needs to be a little grown up to display the actual feeling and actions of the characters.
You get great messages from Splinter. My favorite of his teachings was in the episode Mutagen Man Unleashed. He told Donnie that he would teach his son to enjoy falling down. He knocked Donnie over many times and finished by asking if he liked it yet. Donnie said he did not. Splinter then stated that you can not make someone like something. I use this all the time. I think about things I like and why no one else does. I think that if I showed them the right video of tmnt, they might like it, but I use that quote all the time. Many quotes go with Splinter and I absolutely love them! They have a way of explaining things through Splinter I would never believe!
*A few spoilers below*
In Annihilation Earth, Splinter is struck through the back with Shredder's gauntlet. As I mentioned before, there was no blood, but we watched him die and the turtles react to it. In the next episode (Beyond The Known Universe) We see a recap of what happened and how the turtles were screaming towards the sky for their beloved father's life. The first 14 episodes so far of season four have had bits and pieces of the grieving process. I find that to help children, if you look at it that way, and let them learn that even the mighty heroes in a half shell will get taken down by emotions. Raphael shows signs of hating himself and wishing he could be someone else. Leo wanted to grow up quickly, but he thinks he grew up too fast and wants to slow back down. Mikey is not stupid like Nickelodeon portrayed him as, but lacks a disciplined mind. Donnie has mentioned multiple times how he wishes he could change himself and be human. He wishes he wasn't the way he was. I could continue writing forever explaining the good and the bad of the show. I'm going to stop here though, because I think I have made my points. They are brothers and they portray that. They are a family and show great family assets. This show helps me with my own problems, and for that I thank them. Go Green Machines!!!!!