Here are 3 resources that I feel any new teacher in my grade/content area should not be without:
Khan Academy is a great online resource for and parent, teacher or student. I use this website all of the time as a math resource for my students. You can type in math concept and find videos that teach that concept. This is great for someone like me that was not trained as a math teacher but is teaching math along with all other subjects now. This is also great for independent study because students can use this resource from home as well. Khan Academy has resources for all subject areas but I use it mostly for math.
Kahoot is a great resource for quizzes and games. They have pre-made games and quizzes for Math, ELA, Science and Social Studies. The best part about this resource is that you can make your own games and quizzes directly from the textbooks you use or the notes you have given to your students. It is a great way to reinforce what they have learned and to help students study for tests.
PBIS World is a great resource for Positive Intervention Behavior Support. You can click on a behavior and get suggested interventions that fall under Tier 1, 2 and 3. There is such a wide variety of suggested interventions that I feel anyone would be able to find something that would work for their student. They also have data tracking and tools that are very useful if your district doesn't already have their own forms that they want you to use. There is also a discussion forum where you can post a discussion question you would like to have talked about or you can go on to one that is already started to get the advice of other teachers that are dealing with some of the same things in their classroom as you are.