That's exactly how I felt when I saw this:
http://2me4art.com/2012/03/23/sophies-art/ (Girl's got SKILLS already! Way to go!)
Lovely in theory, impossible in practice for me.
So, thought I, let's just use printable mandala coloring sheets and trace the pattern that makes us most happy, and then color in with sharpie markers like the original idea! That's exactly what we did. :)
First, taped down the corners of large sheets of wax paper to the table (if your artists are prone to messiness, you probably want a plastic table cloth, too...we chose to tempt fate, as usual). Then, slide your printed mandala of choice under the middle of the wax paper and trace with a bold black Sharpie.
(I ran a small fan beside the table, because the marker fumes probably aren't the greatest to inhale...in nice weather, an open window would do nicely.)
Then, we filled in the pattern with colored markers! (I own a ridiculous collection of Sharpies, but you could make a nice pattern with just three or four colors.) The trick is carefully coloring right up to the black line, but not crossing it, or the colors smear. Good fine motor skill practice, good concentration skill work.
(The very small of us used watercolor paints, since they wash out more easily...this is Grace's "Ocean with coral and lots of fish!")
Lark chose a slightly less complicated pattern that suited her attention span. :)
|in the rain|
|in the sun|
Not quite as cool as DIY artwork, but a fun thing to do on a rainy afternoon. :)