Nearpod makes presentations possible in a way that was previously impossible. It gives the presenter controls that they wouldn't have with a standard PowerPoint presentation (and it's free). Teachers send the digital presentation out to student devices and control what students see. Students interact and respond to the presentation, and the teacher can monitor student progress.
This social bookmarking site is easy to use and also provides you with an iPad app, android app, and a Diigolet bookmarking tool. You no longer need to save in your favorites just bookmark all of your favorite sites into Diigo and share them with friends, organize them in lists, or present them with their webslide creator.
They even offer a Teacher console where you can create groups for your classroom. This allows you to have student accounts, without the need for an email address, and then your students can work in the same list, create individual lists, and share everything with only others in their group or publicy (if you choose).