One of our favorite blocks from Grade 4 was the Norse Mythology Block.
There are a lot of wonderful blogs and websites to help inspire creativity, but my favorite books are listed below. Padraic Colum's book is a fine read to fluff out more details for when you are telling one of the myths to your child. But for drawing inspiration, the D’Auelaires book was fantastic!
Here are some of my chalk drawings. I have yet to find the other stories we did - they are buried in my photo log somewhere - but here is something to get you started! I used the D'Aulaires' Book of Norse Myths for the drawings. They are just stunning and even more so when you get them on the chalkboard. The cover world is a nice starting point before you being the tales so you and your child can familiarize yourselves for further enjoyment.
Here is from Yggdrasil, the World Tree...
Some wonderful more thorough coverage of this block can be found at these links:
Waldorf Homeschoolers: http://www.waldorfhomeschoolers.com/norse-myths
Sure as the World: http://sureastheworld.com/2012/04/11/norse-mythology-block-2/
Homeschooling Waldorf has some beautiful wet on wet watercolor paintings that may inspire you: http://homeschoolingwaldorf.wordpress.com/2011/04/28/watercolor-painting/
Sorry I have such little time as of late to showcase more of what we are doing, but I am happy if you can find even a little inspiration from our journey!