Desmos
Desmos is an online graphing tool that is great for both students and teachers! Desmos is free to use and is a great tool for any math course. It can be found online at www.desmos.com or it can be downloaded from the app store.
Khan Academy
Khan Academy is an amazing resource for not just math but any subject! It has so many helpful videos and practice problems for K-12 as well as college level courses. This resource is free to use for teachers and students. It can be found at www.khanacademy.org.