For those who are planning to visit Athens (or have already visited) and are interested in what Athens was like in the 5th century BC, I recommend this video published by Ancient Athens 3D.
And if you go to Athens with your kids, a good way to prepare them for what they are going to see
https://www.youtube.com/watch?v=ulAxMLJ7O7M
Tons of historical information about sites and monuments are also available on the 100% non-commercial Ancient Athens 3D website