It is easy to convert your touchscreen Chrome book to a Drawing Tablet, you just need two simple steps:
Rotate your screen 180 degrees so that is appears upside down: There is a quick-key combination:
Hold Down: Shift+Cntrl.... now press the Refresh button and your screen will rotate 90 degrees each time!
Now open your Chromebook so it is entirely flat and turn it upside down on your desk. Now the keyboard will be a the top and you can easily access the touch screen (which is upside down - but right side up to you now :)
2. Try using a stylus as as drawing tool. Below are the ones I purchased for class on Amazon, inexpensive and work great!!
Link to Amazon for Stylus Pens
This is a great - EZ to use App to try out your new Stylus skills