some hints about programming in graphics

Theme: make your coordinates flexible when possible
Boxes1.py Boxes2.pyBoxes3.py
from graphics import *
def main():
    win = GraphWin("boxes", 500, 600)
    box1 = Rectangle (Point(0,50), Point(50, 100))
    box1.setFill("green")
    box1.draw(win)
    box2 = Rectangle (Point(0,100), Point(50, 150))
    box2.setFill("red")
    box2.draw(win)
    box3 = Rectangle (Point(0,150), Point(50, 200))
    box3.setFill("blue")
    box3.draw(win)
    win.getMouse()
    win.close()
main()
from graphics import *
def main():
    win = GraphWin("boxes", 500, 600)
    box_x = 100
    box_y = 25
    box1 = Rectangle (Point(box_x,box_y), 
           Point(box_x + 50, box_y+50))
    box1.setFill("green")
    box1.draw(win)
    box2 = Rectangle (Point(box_x,box_y+50), 
           Point(box_x + 50, box_y+100))
    box2.setFill("red")
    box2.draw(win)
    box3 = Rectangle (Point(box_x,box_y+100), 
           Point(box_x + 50, box_y + 150))
    box3.setFill("blue")
    box3.draw(win)
    win.getMouse()
    win.close()
main()
from graphics import *
def main():
    win = GraphWin("boxes", 500, 600)
    box_x = 100
    box_y = 25
    width = 200
    height = 50
    box1 = Rectangle (Point(box_x,box_y), 
           Point(box_x + width, box_y + height))
    box1.setFill("green")
    box1.draw(win)
    box2 = Rectangle (Point(box_x,box_y+ height), 
           Point(box_x + width, box_y+ 2 * height))
    box2.setFill("red")
    box2.draw(win)
    box3 = Rectangle (Point(box_x,box_y+ 2 * height), 
           Point(box_x + width, box_y + 3 * height))
    box3.setFill("blue")
    box3.draw(win)

    win.getMouse()
    win.close()
main()