How long did it take you to get an interview for a school nurse position?

I'll admit I've only ever applied for 3 positions; All 3 called within days of me submitting my application to set up interviews. 

A good rule of thumb for any job seeker is to follow up with an email to the hiring manager (or whomever you submitted the application to) a week after submission if you haven't heard anything. You don't want to seem pushy, but for a position that has many candidates, it shows initiative. I would call or email and keep it short and simple - "Hi, My name is @BelleRN. I submitted my resume and cover letter for the school nurse position at ABC Elementary around a week ago and am just following up to confirm receipt and make sure you don't need anything else from me! I'm really looking forward to hearing more about the school and the position itself. Thank you for your time!"

I'll also add that a handwritten note, snail-mailed the day of your interview is never a bad idea ?

Good luck!

@k1p1ssk sorry it's my first time responding on this site and not sure if I'm doing it right but thank you for your advice! 
 

I've been in contact with HR because I asked them how to start the process for school nurse certification. They sent me steps on how to go about this such as fingerprinting and getting my Washington RN license, but haven't contacted me for an interview.
 

That being said, how do I follow up with them on an interview when I've been in contact about the application process? I wonder if they won't consider me until I have the school nurse certification and fingerprinting done?

"School Nurse Certification" is different in every state, so I can't speak to Washington, but if the job description states that you must be certified, then it's possible they won't consider you, but many districts (at least in my state) give you 3 years from hire to get certified. 

Being a school nurse (from the professional standpoint) is complicated. In Massachusetts, the job descriptions often ask for you to be "certified" but what they really mean is "have professional status" from our Dept. of Education. So, for the job title "School Nurse" you not only need your RN & BSN, but you then need to register for an educator license as well. You can apply for your "initial" license almost immediately, but then you need to work for 3 years, full time, and simultaneously, complete a Master's degree in Nursing OR pass the national board certification exam (which you cannot take until you've hit a certain number of work hours, but if you pass, it adds NCSN on to your credentials). With one of those 2 things in hand + 3 years of work since your initial license, you can apply for your "professional educator's license". Once you have that status, you can get hired anywhere.

But, in NJ, they make you take a Master's level Certification Course which is only offered by a couple of schools and costs around $15k. I think there are other requirements as well. It borders on ridiculous at times, the hoops they make aspiring school nurse's jump through.

If I were you, I would go to nasn.org (National Association of School Nurses) and find the Washington State affiliate. Their website should hopefully have a guide to becoming "certified" in WA, or at least someone you can contact for help!