Here are three great videos on the Lego EV3 Touch, Ultrasonic and Color sensors. Click on the “Playlist” button on top of the video player to see all the videos.
[youtube https://www.youtube.com/watch?v=videoseries?list=PLa6Z3d19PjFFklqRSSLzZI5yGv6-3EOXE&w=853&h=480]