Google is constantly finding ways to assist teachers in the classroom and this is just another example of something that can really improve the learning that is already taking place. Using Google+ and Hangouts, schools are able to take part in virtual field trips to places they would never get the chance to visit. All without having to leave their classroom or pay for transportation. http://connectedclassrooms.withgoogle.com/ will take you to their site which shows some of the upcoming field trips. There are a lot for science classes but all subject areas are represented.
An upcoming (as of this writing) field trip focuses on the Emerald Ash Borer. This is a major invasive species in the United States and is one that is often discussed in biology or environmental science classrooms. The students can interact with people from the Chicago Botanic Garden and ask questions of experts in the field, instead of just reading about old information from a text. These type of experiences can have a great impact on engagement and when students are engaged, they tend to learn more effectively.
You can even access old field trips and rewatch them. This removes the interactive component but you can still focus in on some great information and interesting situations. Look over the schedule, for future and past events, and you might find something that creates a learning opportunity for your students.