Go to: nearpod.com
I'm a... lesson delivery tool that allows teachers to add interactive features (like questions/quizzes, polls, videos, and drawings) into their presentations. You can upload your existing PowerPoint presentations and embed checks for understanding right into your presentation. I provide awesome data-tracking to provide teachers real time information that can inform instruction and remediation.
Check out how other teachers are using Nearpod by exploring the Nearpod's Lesson Gallery.
Straight from Nearpod: Nearpod has over 40 guides to walk your though every step of creating a complete Nearpod presentation. Check them out.