Permissions and Safety

I have been thinking about all the new technology pieces that I would like to incorporate into my classroom over the next year or so and began wondering how do I make sure I create safe environment for my students? What kind of permission do I need from parents? From my principal? What are the districts guidelines for all of this? I know that each item has its own safety features, such as if things are viewed publicly or privately. On the other hand, I also want to make sure that my students and parents can access things quickly and easily. If there are a lot of hoops to jump through it is less likely that they will get on and participate.

And then, what kind of permission do we need from parents. Do parents need to sign something that it is okay for their students to comment on a blog? Participate in a voicethread? Get onto a Wiki and check their homework? These are all questions that I am unsure of the answers to and realize that I will really need to do some research into this to find those answers. I just want to be able to make access to these resources easily available to my students and their parents while also ensuring that my students are being protected on the internet.