The bonus assignment is anything that you want it to be for research or world-building.

World-building might be what it is that makes this world different from the real world (even if it is just that these characters exist). Finding pictures of the buildings that exist in the world where your settings happen (Google earth for an address of choice), catching pieces of the news that might enter into the story (Hurricane Matthew is a category 4 storm and a couple Wisconsin people on the news likened it to sitting through a blizzard), or even just getting a good handle on what it is that makes the part of the world where this story takes place different from other places. (Example: they say coke in Kansas, whether it's pepsi or root beer or anything else.)

Research could fall into those categories, too, and it might also be whether your antagonist could balance four blocks on his nose while reciting the alphabet backwards or it might be if your protagonist could logistically run the fifteen blocks between where her friend said she would be and where she actually ended up.

All of it is individual to your story - whatever you need to make it real..