You will get a ton of responses with good info. For your son, the most difficult part might be curating the topic so it can fit within the time he is given.
Depending what topic he picks (who did it, why did the towers fall, how it was covered in the press, the NYC victims fund and lawsuits, Israeli art students, my pet goat, etc.), this might be useful: an airplane (a B-25 bomber) crashed into the Empire State Building in 1945. It only killed 14 people and the building survived. Here is a video summary if he wants to compare the events: https://youtu.be/BfWB9HpoRXo
You will get a ton of responses with good info. For your son, the most difficult part might be curating the topic so it can fit within the time he is given.
Depending what topic he picks (who did it, why did the towers fall, how it was covered in the press, the NYC victims fund and lawsuits, Israeli art students, my pet goat, etc.), this might be useful: an airplane (a B-25 bomber) crashed into the Empire State Building in 1945. It only killed 14 people and the building survived. Here is a video summary if he wants to compare the events: https://youtu.be/BfWB9HpoRXo