Recipe(tried): Chocolate Chip Cookies (starts crispy goes soft)

Judy, I really don't have a clue as to what I'm doing wrong, but this is supposed to be a crisp cookie. Here's the recipe.

2 1/2 cups flour
1/2 tsp soda
1/4 tsp salt
1 cup brown sugar
1/2 cup white sugar
1 cup butter
2 eggs
2 tsp vanilla
1 (12 oz.) pkg. chocolate chips

Cream together butter and sugar; add eggs and vanilla. Mix in dry ingredients and chocolate chips.

Drop by spoonfulls on ungreased cookie sheet and bake 15 minutes or till golden brown. Transfer immediately to cool place.

Not what the heck am I doing wrong with something as simple as this one?? Don't laugh but today I layed them (what I could get apart) on a cookie sheet in the window sill hoping the sun would dry and crisp them up. So far no deal. Thanks Candy, Sad in Ohio.