How I Use It
I use twig as a reference site for students. The website that I use for lessons has links to specific videos or groups of related videos that are relevant to what we are covering in class. Students can use them during lessons or at home to check their understanding. It tends to be most useful when the students are ELL or the material is something that we haven't covered for a while and they just want a refresh. Being 3 minutes long, and visually pleasing, makes the clips ideal for this.
Although there is varied content, some topics have many more resources than others. The videos are too simple for stretch activities and the experiments are instructions, there is no requirement for students to figure anything out, but they are useful as a reference guide.
I have created youtube playlists which do a very similar job as the twig videos. Finding appropriate videos can be very time consuming though and twig is very quick to use and easy to navigate.