Kahoot is a great resource for any teacher at any level! The students use this interactive quiz forum for anything. You can use this as a front-loading activity, a review before a test/quiz, an interactive note session, etc. Kahoot is fun and it's engaging! I use it as review before we take tests/quizzes and as a review if we've stopped doing something for a long time and need to get back to it but review beforehand so the class can recall what we learned previously.
If you are lucky enough to have your administration pay for this subscribtion, use it! I have used this as a means to send both positive texts home and negative texts home. It's easy to use and so fast! Plus, you can just scan the students card and the text sends automatically. If your school uses this, utilize this resource to the fullest!
Google Voice was brought to my attention at the beginning of the year. When SSICA just doesn't cut it for giving feedback to the parents on their students, Google Voice comes through! It assigns your account a phone number which you can use from your cellphone to text parents or call them. You can customize the message (something you can't do in SSICA) and give some real feeback to the parents that's unique to their child. You can also save all of your conversations to keep a running tally of all the information sent on any given student, as well as keep siblings together.