I am a huge fan of Youtube. It is a great motivational source to incorporate in our lessons. We have just started a unit on Westward Expansion, and our kids are going to be keeping a journal. I just found the perfect video to introduce this to my students.
YouTube has a lot of great short clips to inspire students, and it is a great way for kids to make a deeper connection and have longer recall of what they are learning. One sight on YouTube is Khan Academy, which is a not-for-profit with a mission of providing a high quality education to anyone, anywhere. Salman Khan has upoaded 1000+ videos teaching everything from SAT Prep to algebra to finance on YouTube. They are free and fantastic tutorials for kids struggling in math, economics, or science. I personally think that YouTube is a treasure trove of teaching videos. Yes, we have to preview the videos, but it is worth it. There is also youtube.com/edu for educators that have videos uploaded with education in mind. YouTube is a great tool if we find videos that compliment our learning objectives. It is a way for teachers to help one another.
I think United Streaming is another good place to find videos. They do not have as many as YouTube, but they are adding daily. It does come with good lesson plans that you can get ideas from, and lots of curriculum ideas about the video. It also comes with student activities. I usually do not use these, but sometimes they can jump start you to something more creative.