Although they can be a sign of foundation settlement, vertical cracks in a foundation wall are not necessarily a sign of serious structural damage in your home. Vertical cracks are often caused by the shrinking of concrete as it cures; if the edges of a small crack feel even as you run your fingers along the sides, this is likely the reason why. However, it's always a good idea to have a professional look at the problem, so you can be sure that the problem is not major before it gets much worse.
Find a good structural engineer!
Best of luck,