Matific is a great site for finding educational resources for Math in grades K-6th. These resources include videos, worksheets, activities, and more w/ an educational portal that allows educators to track student progress. Also, teachers are using this to assess students performance in Math and differentiate instruction. There is even a free mobile (iOS/Android) app for El Ed math games.
I highly recommend checking out Matific by clicking here!!!
Click here for the iOS app.
Click here for the Android app.
For a more detailed review check out Edshelf.
For my Pinterest board on Educational Resources click here.