My Take
I would add that this website includes a fairly tedious set-up as you have to build the whole thing - your lessons, your curriculum, your student lists, and assessments and I find it is annoying that if I move a student from one class to another their ENTIRE data is erased. Since using this website I have introduced it to my colleagues and among my network.
How I Use It
This free teacher planner has the option for a paid collaboration tool add-on but I use it to keep all my resources together in one place digitally. I am almost into my sixth year teaching and this is the first tool I came across that will allow me to plan from any device, but I can track attendance, grades, and more. Honestly, the pieces you get from the free product have helped me improve my teaching.
*edited to add: my selections for student engagement is not representative of the website because the students/parents don't use the free version. It's a planning and teaching tool.