I really enjoyed it considering it's a holocaust movie, and I think it's definitely worth watching WITH tweens and teens. It's really two stories intertwined - one from WWII and one about a journalist in 2009. Not a party-mood movie, but a very good movie, a very beautiful thought-provoking movie. The main character's actress was great, but I think the little girl who played Sarah did an exceptional job. Be prepared to hit pause several times to answer your kids' questions or to just talk about what is happening in the story - great opportunity for learning and meaningful discussion (including topics usually associated with the holocaust, also abortion and depression). Even if you think you know your WWII history, you may be really surprised at what you will learn in this movie.
My 12 y-o son is not easily entertained, and usually doesn't care to watch "grown-up" movies unless they are high action or full of aliens, etc. Sarah's Key kept his interest the whole time, and he couldn't even keep up with all the subtitles when they were fast because he has dyslexia. Sometimes he'd ask me about whatever he missed and I'd pause it to explain, and sometimes I'd pause it and ask him if he understood what was going on and we talked about some of the things that rarely get discussed between teens and parents. He made it clear he did not "like" it because it was sad, but after it was over we talked about the bright spots, however small and few, we can find even in that story and in terrible tragedies such as the holocaust. Sometimes you have to see the big ugly picture to be able to appreciate the "small acts of kindness" given by some who were put in a tough position, and the amazing courage and love that some people showed during WWII.
The scene with a teen girl and a tween girl swimming naked that is mentioned in the review from this site is COMPLETELY INNOCENT and there is nothing provocative about it at all. The girls were desperate for a cool bath and they had on their panties and it didn't show the older one close up, and the younger one had "no chest" and the water was muddy anyhow, so there was really nothing to see.
Caution: If you have a child who is very easily scared, you should fast-forward through the part *SPOILER ALERT* where she finally gets to use her key. The inside of the closet is never shown, but the look on her face and her screams are very dramatic. Or you could have your kid go get you something to drink or take a bathroom break, then mute the TV and let it get past the point of her screaming - it's not long. Compared to what most kids see on TV and movies it's nothing, but I wouldn't have wanted my kids to see it when they were around 10 and under.