Will glasses improve my short sightedness, resulting in me not having to wear them as often?
There is no evidence to suggest that wearing glasses for a limited period actually alters or improves your eye sight.
Short sightedness, or myopia, is caused by the shape of the eye - either the eyeball is slightly too long or the cornea (the clear covering of the front of the eye) is too steeply curved. Glasses and contact lenses are able to correct the refractive error but not the cause, but there are several methods which can "improve" your vision permanently which include refractive surgery.
If you would prefer not to wear glasses, perhaps you should consider contact lenses. There are various lens types available which can be worn for varying lengths of time. Your local optician will be happy to advise you on the most appropriate contact lenses for your prescription and lifestyle and answer any of your other questions.