The Internet makes it easy for teachers to network, view video examples of colleagues' work and even make some money sharing their own work with others. Sifting through lesson plan resources online can be a daunting task, but the good news is that there is a lot out there and much of it comes free of charge.

Every teacher is only a few clicks away from a vast community of educators who share common goals, face the same challenges and continue to search for similar solutions every day. 

Education Dive keeps tabs on a wide range of online resources for educators, and these are 19 of the sites that impress us the most with their lesson-planning libraries:

1. LEARN ZILLION

LearnZillion was created to provide support for schools, teachers and students in the nationwide transition to the Common Core Standards. LearnZillion recruited a "Dream Team" of 123 of the country's best teachers to dissect the Common Core Standards and create a wealth of lesson planning resources. LearnZillion is free for teachers and currently has 2,000 lessons online, including year-long curriculums.

2. ENGRADE

More than a mere lesson planning website, Engrade is a comprehensive educational platform with lessons, worksheets and gradebooks. Engrade's wiki section contains lesson plans and study guides created by teachers; the flashcards section has flashcards and quizzes to help students study. Free for teachers and students, Engrade is supported financially by its Engrade Plus platform, which provides subscribing schools with student data and performance tracking. Also see All Think, Engrade's educational video production and sharing resource.

3. SHARE MY LESSON

Developed by the American Federation of Teachers (AFT) and the Times Educational Supplement (TES), Share My Lesson was modeled after TES Connect, the largest online teacher's network. Share My Lesson has over 250,000 free user-generated resources, with multidisciplinary lesson plans, worksheets, presentations and activities designed to meet Common Core Standards for all grade levels.  

4. BETTER LESSON

Founded by Teach For America alumnus Alex Grodd, BetterLesson is a free space where teachers can connect, collaborate and share lesson plans. Like most of the educational platforms on this list, BetterLesson's basic resources are free, while the more advanced resources are available to schools and administrators for a fee. 

5. THINKFINITY

Developed by the Verizon Foundation, the Thinkfinity online platform offers free K-12 lesson planning, course material and classroom activity resources aligned to both state standards and the Common Core. Each subject's resources are created by specialized content partners; for example, the economics resource was developed by the Council for Economic Education while the math resource was developed by the National Council of Teachers of Mathematics. The end result: a comprehensive and multidisciplinary resource that is applicable to almost any classroom. 

6. READWORKS

Billed as "the solution to reading comprehension", ReadWorks is a free resource for schools and teachers with classroom-tested Common Core-specific lesson plans aimed at closing the achievement gap and dramatically improving literacy in grades K-6. See Free Reading for literacy activities and Handwriting Worksheets for handwriting activities.

7. THIRTEEN ED ONLINE

Created by PBS's New York Channel 13/WNET, Thirteen Ed Online provides education technology resources, multidisciplinary lesson plans and teaching activities for teachers and schools. Membership is free.

8. PBS TEACHERS

Similar to its local substations, PBS provides a vast range of pre-K-through-12 resources. Teachers can access lesson plans and classroom activities from a variety of sources that have been aggregated on the PBS Teachers website. 

9. THE LIBRARY OF CONGRESS

The Library of Congress has classroom-tested lesson planning and classroom activity/presentation resources, as well as a wealth of primary source materials. As a teaching resource, the Library of Congress is particularly valuable for social studies classrooms in middle and high school.

10. FEDERAL RESOURCES FOR EDUCATIONAL EXCELLENCE

FREE, as it is more commonly known, is a database of aggregated teaching resources from federal agencies. The site contains material for a wide variety of subjects in K-12 classrooms.

11. THE GUARDIAN'S TEACHER NETWORK

A user-driven online community for teachers, The Guardian's Teacher Network was created to bring together educators across the United Kingdom. While the content is geared towards UK teachers, the Teacher Network has over 70,000 teacher-created resources that are functional in any classroom, in any country. 

12. THE TIMES EDUCATIONAL SUPPLEMENT

Since 1910, The Times, a British daily national newspaper, has published the Times Educational Supplement (TES). TES is the world's largest online network of teachers, with 2.2 million registered users in 197 countries and an arsenal of more than 500,000 teaching resources. Although TES was designed for UK educators but it contains an abundance of valuable resources for any educator who knows just what they're looking for. The site's materials are free but e-mail registration is required for access. 

13. BBC TEACHERS

Similar to the Guardian's Teacher Network and the Times Educational Supplement, BBC Teachers is an educational resource for the UK schools system. The lesson plans and teaching materials, however, are applicable in almost any classroom. 

14. TEACHERS PAY TEACHERS

Teachers Pay Teachers is an open online marketplace where teachers buy and sell lesson plans and teaching materials, mostly for pre-K-through-12 classrooms. The website was created by Paul Edelman, a former middle school English teacher in New York City, as a response to the difficulties of lesson planning and the lack of usable online resources. Now, there are over 1 million registered users, over 50,000 free resources and over 300,000 materials for sale. One particular success story is Deanna Jump, a kindergarten teacher in Warner Robins, Georgia, who earned $1 million by selling her extraordinarily popular materials using the site.

15. TEACHER LINGO

Similar to Teachers Pay Teachers, Teacher Lingo is an online community where teachers buy, sell and share teacher-created resources. Created by Betty Miller, a retired sixth-grade teacher from Texas, and Preston Ridley, her son-in-law and a software developer, Teacher Lingo was originally started as a forum where teachers could share their experiences and collaborate as educators. As lesson plan sharing became prevalent, Teacher Lingo transformed into a prominent educational resource marketplace for teachers.

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