Watercolour painting is very popular, yet is very difficult for the novice to learn. I have tried it. I have taught it, and I still find it mesmerizing. Watercolour involves the layering of colours, from background to foreground, and accounting for all those little technical details in between. It is one of those processes that involves extensive planning and thinking ahead; planning what to do, and deciding when you want to do it, to achieve the desired effect; unlike oils or acrylics, where you can easily paint over a mistake. It is very unforgiving!
Here is a list of the most common terms and techniques to teach your novice watercolour artist, and a lesson on how to demonstrate the most basic effects.
Yes, watercolours are a bit messy and troublesome. But it is a technique unlike any other, and every student ought to have a chance at working it. This lesson requires a higher skill level than primary elementary.