Properly brought up Mathematicians are rather dubious of this approach -surely, they say, a careful explanation of everything is essential. But it isn't. Students are going to learn about Mathematics not Mathematica. I have been through most of it. The first section of Functions and Graphs exploits the Plot command.
Many students are vague about functions.
The section Series 1 dealing with sequences uses Table and ListPlot to generate pictures of sequences. This allows you to see what is going on. It really is helpful. You can use it to look at all sorts of sequences, not just the standard ones in all the books. There are nice sections on recurrence sequences, binomial expansions and polynomial approximations.