If you're just taking it to 'class and back', the DTR above that CScottG posted is likely to be a pain. Not only is the laptop heavy, so is the power brick, and the footprint is equally large, and they tend to be fairly loud in use (fans); and that's saying nothing about the actual quality of the keyboard and touchpad, which are two of the most important things on a laptop, as well as the overall build quality and how well it'll handle being shuffled around.
I'm not a fan of DTRs unless they're doing exactly that: replacing a desktop, and moved sparingly. That they do fairly well.
You really need to see just what you're looking for. Go into any electronics store and play with what they have. Annoying, sure, but this is something that you'll regularly have to use for work, and it's worth getting something good.
And do note that you do not need fancy specs for what you're looking to do. Basic CAD is not demanding, and for the demanding stuff you'll likely be learning in a lab with computers suited to the task. Focus on purchasing a tool that can handle being shuffled about while providing a pleasurable user experience.
Canon 6D|24-105/4L |70-300/4-5.6 IS USM|50/1.4 USM|50/2.5 CM|50/1.8 STM|85/1.8 USM|Samyang/Bower 14/2.8|24/2.8 IS|Sigma 150-600 | C
Canon EOS-M|11-22 IS|22/2|EF-M 18-55