I used one custom block: draw square at size (size). Every square drawn is centered; I defined the custom block that way. Size = length of one side. Couldn't figure out how to let the user determine pen color ^_^ Recommended size between 40 and 360. Otherwise it would be too small or too big. Use the grid background to help. View another related project with this link: https://scratch.mit.edu/projects/169000562/
