If you want to be the best possible librarian you can be, you must take responsibility for your own professional development. You might feel it isn’t fair, since teachers don’t have to do this, but fair is not the issue. The only way you will get what you need is to seek it out yourself.
To stay current with constant changing world and learning how to integrate the latest trends and technology into your program, help teachers, and continue to prepare students for their future, you need to pursue relevant professional development. “Relevant” is the key term since most districts provide professional development several times a year. While these are helpful in understanding what is being required of teachers, they rarely are directly helpful to you and your program.
Free PD
Your first concern is likely to be cost. Teacher PD is usually paid for by the district, but this isn’t true for librarians. However, you don’t have to let this stop you. We just have to be more creative. And the long term and professional cost of not finding ways to include this is potentially very high.
Your colleagues can often be a source of highly relevant, useful information. There are numerous Twitter Chats you can join with different themes and days and times when they are held. This Piktochart infographic has several excellent ones. For an explanation of how the chats work and brief descriptions of some (including a few from the Piktochart infographic) go to Top Twitter Hashtags for Librarians.
Library magazines such as School Library Journal frequently host webinars. They are normally held in the afternoon so may be impossible for you to attend live, but most make the archive available to listen to at a more convenient time. You can pick and choose which ones are of greatest interest to you. Since these are free, you can’t always find exactly what you want, but you may discover something you hadn’t considered.
AASL offers some free webinars through their eC0LLAB page. For example you can choose “A 21st-Century Approach to School Librarian Evaluation” or “A School Librarian’s Role in Preventing Sexting & Cyberbullying.” Two excellent possibilities are the ones on the 2015 “Best Apps for Teaching & Learning”, and “Best Websites for Teaching & Learning.” The webinars discuss some of the winners for the year and give you great ideas to use with your teachers and students.
Occasionally a publisher hosts a webinar. These are always free, but obviously they have a product to sell. It doesn’t mean the webinar isn’t worthwhile. If you are curious about the product, it’s no different from seeing a presentation at a conference.
Quality PD at a Range of Prices
The best source for relevant professional development comes from your state and national library associations. In addition to the free webinars AASL offers, they also have online asynchronous e-courses. The AASL e-Academy offers a number of options. A four-week course is $119 for members, $245 for non-members, and $95 for student AASL members. Courses are offered on a rotating basis, so if one you are interested in is not being offered in the near future, you can contact Jennifer Habley at AASL and she will let you know when it will be scheduled again.

ALA editions offers e-learning in the following areas: Computing, Technology, & Web Design; Copyright; Management; Programming, Outreach, Marketing and Customer Service; Personal Development; Reference; Cataloging and Metadata; Collection Development; and Information Literacy and Library Instruction. These are all connected to books published by ALA and part of the cost is for an e-book that goes along with the course. For example under Personal Development you can see a course I am teaching “Being Indispensable: A School Librarian’s Guide to Proving Your Value and Keeping Your Job” which is a 6-week asynchronous course and will start on July 18. Prices vary from one to the other, but this course is $195. I am currently teaching one on New on the Job and it is $245.