This hugely popular and highly social collection of online multiplayer games is coded and designed by the players themselves, then shared with the rest of the Roblox community. In the wake of the Coronavirus pandemic, the company has been adding more curriculum and educational games to its teaching resources, with featured lessons including an introduction to coding and game design, how to create multiplayer maps and coding basics like arrays and strings. Give it a try and let us know how it goes!
https://education.roblox.com/en-us