A cover letter is always professional. Just try to remember to customize the letter (with names of management and store name ect). Try and keep it simple though. You are applying for entry level positions where a cover letter is not required, however, a nicely composed cover letter will set your resume apart from the dozens they probably receive. Always remember to keep it focused, to the point and address it to the individual or management person whom you want to receive it. A quick phone call ahead of time to find out the hiring manager's (or the human resources manager's) name is always helpful. That way you can address your letter directly to them, which lends a personal touch with attention to detail -a trait all managers look for.
Good Luck!
Good Luck!
