DESMOS 

Online graphing and scientific calculator.https://www.desmos.com/

KHAN ACADEMY 

Online lesson tutorials with videos and practice exampleshttps://www.khanacademy.org/

ONLINE CALCULATOR: meta-calculator

  Go to https://www.meta-calculator.com/ and choose the kind of calculator you need to use. Very helpful when doing assignments at home that require more than just basic scientific calculator.