Here are a few of my favorite online resources:
Peardeck
Peardeck is a Google Slides "add-on" feature that allows for the creator to insert interactive questions. I especially love using Peardecks for test reviews and daily warmups. Bring able to watch students answer questions live is helpful for individual formative assessment. I also enjoy being able to show student work, both annoymyously and by name.
Kami
Kami is a Google Chrome extension that is useful when going through worksheets or examples that you would like to save as a PDF. Kami allows you to upload materials directly from your Google Drive in order to draw, type, and/or highlight on them. I find Kami especially helpful in tutoring sessions where students want to review specific homework pages. This resource also makes handouts accessible for at-home learners who don't have access to printers.
Kahoot
Kahoot is a resource I like to use when I want to review vocabulary, times tables, or similar topics. I like Kahoot for this because it adds a competitive aspect to questions where students don't neccessarily have any work to show.
IXL
IXL is an online resource that directly corresponds to TEKS. This resource is a great way to incorporate differentiation into online assignments, because it will adjust the amount of questions asked depending on the questions answered correctly.