What would you put in a shadow box?

For Christmas, I got a shadow box and I want to make it for my dad, but I%26#039;m not sure what to put in it. I was thinking about pictures, because I definitely wanna put some in it, but what other things could I get to put in it to make it look more like a scrapbook?|||what does he like ? what are his hobbies? does he like old coins, model cars, or boats? use what you know about your dad.|||If your dad has things that mean a lot to him like his dads watch, medals he got in the military, awards he%26#039;s saved from his childhood or work, things of the sort mount them in the frame for him he%26#039;ll love being able to display them rather then hiding them in a box orr drawer