The rights for some video content have recently changed, which has shortened the window during which some content is available for streaming. This is the result of the complex environment of rights and digital distribution, which involves a number of different entities and specific contractual obligations that can vary title by title, all within the context of changing technologies and significant operational costs. We regret the inconvenience you have experienced.
Due to such factors as rights and technological infrastructure, PBS is not able to keep all programming available via streaming indefinitely. However, our system is fully committed to providing access to local and national content for a significant period of time after a program airs.
Overall, hundreds of hours of recently broadcast programming, as well as past episodes of popular series, are offered for streaming on station web sites, other locally offered platforms, as well as on PBS.org and our mobile apps. In addition, a deep archive is being maintained for certain genres, such as news, public affairs and independent film, including such series as FRONTLINE and PBS NEWSHOUR.
Recognizing that many teachers include PBS content as part of their lesson plans, we are working with producers to extend access to episodes that are particularly popular with educators. In the meantime, you may be able to find helpful resources on PBS LearningMedia, an on-demand service that provides thousands of innovative, standards-aligned digital resources, compelling student experiences, and professional development opportunities for teachers.
More information is available at: http://www.pbslearningmedia.org/about/products/teachers/.