I think Blender is a great program. Just so you now, in case you have not seen what Rhino does. I have unfolded many vehicles and models for people who have modeled in Blender. As Rhino is a CAD program, it is good for making real things, like the Space Shuttles tiles, which were modeled in Rhino, to boats and airplane parts. Non Uniform Rationale B Splines is at the heart of what Rhino does. Being able to create 3D shapes from 2D drawings is a fantastic thing. Also, this is a program that is compatible with many types of machinery, Faro Arms, 3D Printing, jewelry design, CNC machinery, etc. I understand preference and also the economic situation going on. If someone did have the $200 dollars though, and the qualifications to purchase Rhino with a student license, which is the same program as the commercial license, you would be wasting your time with Blender. Blender is far less intuitive, has a much steeper learning curve and it's formats are limited as it's abilities.
If you can squeeze out $200, don't waste your time with Blender. If you don't have the money, different case.
The first few pictures below are just some simple exercises that takes 15 or 20 minutes in Rhino. All parts unfold. Some of these models are far more complex, but all the parts unfold and will make a model. The last few models would be very difficult to do with Blender, if not impossible.
I respect your decision, but remember that Rhino can be had at a student fee to anyone as long as they are a student. They have had this offer for many years. Since it is used in industry, in Hollywood, and in many design firms, and in manufacturing. I have 16 years of experience programming 4 and 5 axis CNC machinery in the Aerospace Industry. Rhino3D is a way of teaching your students with a program that is world known and established. It is something you might want to keep on the back burner. Also, you can download and use it for 30 days, for FREE. At which point, it remains fully functional, but will not save. Using the Print Scrn function and a program like XNView, you can still make models with it, as you can capture the images to the Clipboard. This means all your students could download it, use it as a viewer for many different kinds of models, FREE. I just wanted to clarify, as I may have given the wrong impression about my experience with Blender, CAD, and real world experience in the use of these programs. The programs are not really comparable. AutoCad is more comparable to Rhino but is nowhere near as flexible, and there are things you can do in Rhino that would be impossible in AutoCad. AutoCad costs a small fortune.