Start by creating your future (at least on of them). You can use a simple 2D matrix, similar to the one I showed in the slide deck in class. You can put anything you like on the two axis and think about what are the possibilities that you'd have in the four segments. Pick a slice of one of more segments using possible-plausible-probable cone frame work (you'll find an example in the same deck.) Describe it for yourself - write a few of paragraphs for your documentation, add some reference images - and start digging around in there for some objects that could represent that future.
Once you pick one object start modelling it in Blender. It will probably take more than one attempt, so for now create one or two rough drafts. You can render them, or just take screenshots, and add them to your documentation.
2D MATRIX
High Tech - Unsustainable
This world is bare and cold but contains a lot of cool futuristic high technology. Imagine that we may even move our civilizations to the moon or other planets where things don't grow. We live off processed food for nutrition purposes only, and machines make the air we breathe. For this world, I envision some sort of robot that will grow or generate the fake food that we eat.
High Tech - Sustainable
This is a lot of the future that we imagine will happen. Flying cars, automatic transportation, and even unique houses that float on water or are located high up in the air. Large open spaces with greenery in the middle of a large city because everything will fit. We are highly conscious about the earth and it's health, while also operating with a lot of technology in our daily lives. For this world, I envision some sort of flying air purifier that will pick up any pollution that is made, and instead generates plant food.
LOW TECH - SUSTAINABLE
This world is very similar to our current world, only much greener. I envision greenery growing vertically and on top of buildings everywhere. Low tech doesn't mean no tech. I instead envision that this world uses a lot of smart technology in our daily lives, but we are still dependent on manual labor, natural resources, and more like today.
For this world, I envision that we have some sort of smart planters that will take care of all the plants growing on buildings.
LOW TECH - UNSUSTAINABLE
This world would resemble something if today's modern world still looked like it did in the industrial times. It's dirty; we rely a lot on manual labor, even though smart tech still exists in some areas. There's an abundance of factories and pollution. We have no care for the environment, nor do we think that it is something that we need to care about.
The item: A air purifier, but it is year 3000, and it can fly
BLENDER MODEL