Preheat oven to 350˚F. Coat baking sheets with nonstick cooking spray.

In a large bowl, combine flour, granulated sugar, baking powder, oil, milk, salt, extract, lemon juice, and eggs. Roll dough into 1-inch balls and place on prepared baking sheets. Bake 12 to 15 minutes, until cookies are set but not brown.
Let sit 5 minutes then transfer to wire rack to cool completely.
 
Glaze
In a medium bowl, combine glaze ingredients and stir until smooth.
 
Dip tops of cooled cookies in glaze and place on wire rack then immediately decorate as desired. Rainbow sprinkles and decorating sugar for topping (optional)

Note: If you want to decorate your cookies with multiple colors, separate glaze into smaller bowls and mix in food colors one drop at a time until reaching desired colors. If you want to add a flavor to your glaze, add a drop of your favorite extract.