An object of footwear for children which allows adults to visually determine whether the shoe proper fits the child and can be adjusted in its effective size when it is determined that the shoe has become too small. The article of footwear comprises a fitting system comprising: (1) a substantially transparent window disposed in a predetermined location in the vamp so that when a wearer who has a foot that properly fits in the article of footwear puts on the article of footwear, a portion of a toe of the wearer can be seen through the window, and (2) a sizing member attached to the upper, the sizing member being placed within the opening against the heel portion to create a first effective size of the article of footwear, the sizing member being removable to create a second effective size of the article of footwear. The present invention also provides a method of determining when to adjust the effective size of an article of footwear and adjusting the effective size of the article of footwear.