Wet on Wet Painting - Hold form?

It was a beautiful day! In the morning we met with friends at the park for a nature walk, followed by lunch with Daddy and rest time. Our afternoon activity on Friday's is wet on wet painting.

 While baby was sleeping Brother and I did our wet on wets using yellow and blue. I painted my picture first. This is a huge learning

experience for me because I don't feel like I am very "artistic" or "creative". I figure that i will learn along with the boys. 

After I model the picture, Brother is supposed to create a picture
inspired by my modeling as his lesson. Then he is free to do what he wishes with a second picture. And it started out that way. He was painting with blue and singing about a snowstorm. Then all of a sudden it changed and he went into a color experience of painting with paint, and then wiping it off with a rag. He did that over and over. After a while he folded the paper as well, creating a huge paint, water, folding, wiping experiment. This was not the lesson and left me with the conflict of "hold the form" and stop the process or let it go on. I felt like the experiment did have value, so I chose to let it go on. His energy was very focused and intent. But after he was finished with this picture. I had him do the second one as the lesson. 

Here is the one from his actual lesson. I like it a lot better than mine. 

Baby woke up part way through the lesson. I just had him use Brother's old paint. What I think is neat is that when he was making those lines, he was pretending to saw with the paint brush and was making sawing noises. His whole painting experience was very cute. He had a lot of fun and really just lived in the color.