The ‘Behaviour Needs’ website is one that I’ve been following for quite a while, I find their advice to be practical and sensible.
They do have a wide range of resources and much of it is either free or very low cost.
It’s not a ‘technology’ resource but I’m sure that many people would find useful – like these fun posters for example.
If you’re interested in seeing some of their more serious work then you could do worse than start with this report entitled Effective Responses For Seven
Common Classroom Management Problems.