Basically I'm an architecture student in second year getting to grips with AutoCAD 2014. How do I go about moving a drawing from CAD to photoshop in order to render it? And how do I then print this rendered drawing at a certain scale, do I have to move it back to AutoCAD and then plot it as normal? Im fine with the actual drawing aspect of CAD but I really struggle with understanding how to plot and how to move files between other programmes. Any help would be greatly appreciated!

Hello daniel2510, if you draw with AutoCAD 3D you can "render" 3D objects directly.
If you declare materials on those objects you can have good aspect rendering.
You are talking of "print this rendered drawing at a certain scale" : is it only a scale of the object or the scale of the rendering ?
For both of the scales it's possible.
Anyway if you want to print rendered you will have to know about viewports in the paper space.
Tell me if this helped or not.
Tell us about your AutoCAD level : 2D beginner, 3D beginner, etc....
You can take a look at sites like CAD TUTORIALS or Infiniteskills for AutoCAD lessons.  

If you take the drawing from AutoCAD to Photoshop for rendering I highly doubt you'll able to bring it back into AutoCAD to print it.

I would say my AutoCAD level is intermediate with 2D , I have no experience with 3D whatsoever. This is an example, I want to draw a 2D elevation of a building, I want to scale it to 1/100 lets say. I then want to put this 1/100 2D drawing into photoshop to do some rendering. At this point I want to print the completed drawing. To do this would I print the drawing from DWG to PDF and simply open the PDF in photoshop in order to render? Would this keep the scale at 1/100 like in AutoCAD?

Daniel2510, if you don't know much or all about 3D it's going to be difficult, and as John said, once you are going from AutoCAD to Photoshop there will be no return ( vector --> image, the image stays an image ).
There are sites to learn 3D as I told you before.
Eventually, see my DWG file : 3D VOLUMES 01.dwg that you can find in the CAD Blocks library right here in the site, you launch a search with the word : 3D VOLUME.
Going from 2D to 3D with just vertical elevation of the "2D" sketch" is not too difficult, but for me you will have to learn all about viewpoint and UCS etc...
I don't  think that you can easily afect exact scales to "images" but if you do it with 3D AutoCAD with viewports then the result will be scaled exactly with the rules of the 3D scales that I don't know if you know them ( isometric example : angles of 120°, vertical ratio of ...... if you know it ! ).
I can help with AutoCAD......