EquatIO 
– Easily create math expressions including equations and formulas
– Compatible with Google Docs, Forms, Slides, Sheets, and Drawings
– Input via keyboard, handwriting recognition (via touchscreen or touchpad), and voice dictation
– Guesses what you’re typing or writing (like predictive text on your smartphone)
– Hear your math expressions read out loud
– Compatible with LaTeX input for advanced users
– Create interactive digital math quizzes
– Input student responses directly into digital quizzes
– Chemistry formula prediction
https://chrome.google.com/webstore/detail/equatio-math-made-digital/hjngolefdpdnooamgdldlkjgmdcmcjnc

IXL Math
This is free and provides a variety of math practice with many worksheets and answer keys. Must create an account and set up your classroom. Pre-k to grade 12.  Supports daily practice.
https://www.ixl.com/resources/learninghub

Kami
Kami is a great tool for annotating on digital or scanned lesson materials, note-taking, and creating assignments. It has many graphic organizer templates. Annotations, notes, and assignments are saved and can be shared through Google Drive so students can access them later.
https://www.kamiapp.com/