I made a submarine in DEEP class and I worked on it in Creator's Studio also. It was very hard but it was really fun. The hardest part was probably the wiring part. Mr. Umekubo helped me so much. I did a lot of things on my on but without his help I would not have been able to finish the construction of the project. The submarine was maneuvered using bilge pumps. Bilge pumps suck in water and then pumps it out. It was great to build!
I also made a boat. To be honest, it is not quite finished but it is coming along. I have taken apart a remote control car and I 3D printed the body of the boat. Once I am done 3D printing, I will put the motor in the hollow body and attach a propellor.