There are further links to online guides etc in this post, on a blog where I gather tech tips/guides....
There are two versions of this - I initially did this without sound, and the video was longer as I rushed to get it online in time for a lesson.
The first video is shorter but actually has more tips and points, as well as a voiceover. Most, not all of my voiceover points are covered by the onscreen titles, so you can always mute the audio when re-viewing this to check on a particular tool or technique.
Keep a log of tools, shortcuts, techniques and general pointers that YOU can refer back to quickly.
VODCAST WITH VOICEOVER
By the time you come to do A-Levels, if you pick Media you'll be creating vodcasts - this isn't the most polished example you'll ever see, but follows the basic framework you'd want: a title sequence, relevant imagery/clips at all times, voiceover doubled up with clear titles (which I've resized to be much bigger than the default in FCPX).
CLICK ON THE READ MORE LINK below TO ACCESS THE VIDEO
earlier vodcast with no voiceover - longer, but less detailed: