This site is the virtual submission hub for STEM School Highlands Ranch and I can verify that it has been created by the technicians at our school. All other URLs affiliated with this site are also safe. In a nutshell, Canvas is like "Google Classrooms" but better.
There are no threats, annoying popup ads or scam prompts. The information on this site is legit, and I know it won't harm your computer because I've left my computer idle on this website for around an hour and absolutely nothing changed.