*This does not have to be the first step in the project! You are more than welcome to do the sensory immersion and then make the papers with those experiences in mind--whatever! I just recommended this way in case you want to do this project all at home and in a few days, because the papers can be drying overnight while you and your kids do the outside stuff and write the poems.*
The first step of the book project is SO MUCH FUN. Seriously, you parents are going to want to do it too--it is hypnotic, calming, beautiful.
Basically, you and your kids just paint a whole bunch of pages of paper with lots of watercolor.
Choose whatever colors you want! Enjoy the sensation of brush and the saturation of colors.
The only rule is that there should be no white left on the paper when you are done.
Get creative and sprinkle salt onto wet papers, blot with crumpled paper towel, scratch with the ends of the paint brushes--have fun and see what happens! And you don't have to use special watercolor paper--use whatever white paper you have on hand! (In fact, we learned from experience that "real" watercolor paper is harder to cut later on because it is thicker--so esp. those of you with younger artists might want to use a lighter weight paper.)
The only other thing I would recommend is to think about WHERE out in nature you plan on having your kids experience their sensory immersion, so that you have made painted pages that you anticipate being helpful to your project. For example, if you know you are going to take your kids to the beach, think about what colors they might find there, and encourage them to make watercolor pages that are sky and water and sand colors, etc. If you plan on taking your kids to the redwoods, then have them make plenty of reddish brown papers and lots of different green papers, so they have plenty for their specific needs.
Don't you or your kids think it won't be fun to stick to just a few colors, if that is what your chosen nature setting requires--it is actually a fantastic experience just to play with how many interesting ways and tones you can paint one color! And this is where they can have fun with textures too. How might they get a sand texture? How might they get a texture that looks like bark? Etc.
I made the above paper a few years ago when my girls and I did this--and this image (which reminded me of roots, when viewed the other way) is what inspired the "What's Above, What's Beneath?" book project we did last year! It's just watercolor paint dripped onto an already damp paper, and allowed to run wherever gravity takes it. SO FUN.
Your kids are going to have so much fun with this part.
And if they want to paint colors you know you won't need for your art--let 'em! The papers can always be used for a later art project! (Remember the watercolor hearts I put in your kids' Valentine's Day mailboxes? Leftover paper from this project years ago. : )
As always, if you have questions, please leave them in the comments below!