Edublocks is one of the few platforms I could find that has a solid teacher dashboard to track and assign work. It also looks very well designed.
Scratch
Even as a Maths teacher I have heard of Scratch, so doubtless you have too, but have all your students yet explored it?
Code.org
Code.org clearly has big aspirations as you can see from the video. The platform does look really good, get your students involved? See if one of them is the next Bill Gates :-)
mBlock
mBlock looks to my eye similar to Scratch. This is no bad thing! It appears from the video that the aim is often to try and move from the coding to a physical project with mBlock devices.
Code for Life
Code for Life helps students learn to code through gaming, working through levels. There is a teacher dashboard, but I am not sure if it really shows you any progress details.
Websites
Websites
Craig 'n' Dave
Craig 'n' Dave sound like top notch guys don't they! There is lots of free content on their website and if you like it a lot, there is more you can choose to buy.
Apps
Apps
Kidlo Coding
Coding games for kids by Kidlo has lots of mini games all designed to help learn how to code. All free and across all devices and desktop!