In our 2.008 manufacturing class, teams of six each designed and manufactured fifty yo-yos. After brainstorming dozens of yo-yo ideas, our team came up with "Sharknad-yo", a yo-yo themed off of the popular Syfy franchise "Sharknado". Our design, a bit larger than a regular yo-yo, took the shape of a tornado and was filled with water and sharks. 
 
Each yo-yo half comprised of a body shell, clear cover, retaining ring, snap cover, and, of course, acrylic sharks. We injection molded most of the parts, along with thermoforming the clear plastic cover and lasercutting the sharks. We also bought rubber o-rings to help seal in the water. We CNC-machined the molds for the plastic parts.