http://worldhistorymatters.org/
World History Matters is a portal to world history websites developed by the Center for History and New Media. This would be used for higher history classes in high school and mostly as a source of informative articles for papers, projects or assignments.
Khan Academy is a non-profit educational organization created in 2008 by Salman Khan with the goal of creating a set of online tools that help educate students. There are lessons, quizes, activities, etc., that are available for students of different levels and different needs.
https://www.canadashistory.ca/
A website of Canada's history in different forms to browse through and educate yourself with. It has resources for all different types of learners and also provides classroom lesson plans, etc.