Jeans, heels and a dressy jacket is one of my all time favorite looks. Those distressed jeans that you used to throw on with your ratty sneaks are now more sophisticated with some great heels and a jacket. Bonus, they are still just as comfy.
A biker or a baseball jacket also make great additions to this simple look.
Sometimes simple is best. A graphic sweatshirt, a baseball shirt, a simple white button down, or even a Texas tuxedo all seem a little more special with the addition of a pair of heels.
You don't have to don sky high heels. Pick the height you like best and go for it. I gravitate more toward lower heels these days but any heel will do. I tend to prefer a simple, pointed toe pump but just Google "jeans and heels" and you'll find lots of additional inspiration.