If you haven't read the trilogy DO. I think I found it more sinister as a parent even the 1st one alone. The idea is an appalling one. Interestingly it reminds me of the way stories have ancient themes and re occur throughout time: the legend of St. George and the dragon with its maidens being sacrificed or sacrifices to the Minotaur in Greek myths and legends. The Capitol and all it stands for are particularly pertinent in our celeb obsessed day and age. There are chilling themes in this book but there is hope too. I think the film, despite having to miss out on the details that build an even clearer picture when reading, conveys that well. Certainly got the thumbs up from us even though I am now having to watch "Strictly" to calm my nerves.
GO SEE IT but also READ IT....you can do both whichever way round you want but it will be worth it. 11+ I feel-there are some scary bits in it and the themes explored are, I think, too unsettling for younger.