Generative art
Canvas
This is an extremely open-ended project. You should do this project if you like making visual art and you want to explore the capabilities of using a computer to make art. Generative art, according to Wikipedia is art “that in whole or in part has been created with the use of an autonomous system”. The autonomous system in this case will be your program.
The basic idea is that you write a program that generates graphics or animations but rather than just writing code to produce a specific image or animation that is the same every time you run the program, there is some element of randomness or other input that causes the output of the program to change in maybe not entirely predictable ways.
This project is an opportunity to go deep on the graphics primitives provided by the HTML Canvas element which are similar to those provide by most computer graphics systems. There's also plenty of good math to dig into if that's your kind of thing.