I feel some explanation may be in order, so here's one from Wikipedia:
This book told of the surreal origins of the Upsys and Downsys. They were once merely flowers, covering an entire world made of fuzzy dandelions. A sentient wind called The Great Huff passed by this world long ago, and, having his nose tickled by the dandelions, blew them all away. As the dandelions fell back to earth, some of them fell through a rainbow, and were magically changed into rightside-up beings known as Upsys. Other dandelions fell through a storm cloud, and became upside-down creatures called Downsys. The two factions, despite each being the others' polar opposite, got along famously, and developed their own little civilization, which came to be known as "Upsy Downsy Land".
Hey, it was the sixties.
Like many children's books, this one was published to advertise a line of toys, in this case, Mattel's psychedelic creatures who inhabited a "Happydiculous World." Each character was packaged with a play-mat that could be connected to another mat for endless happytime opportunities.
For a few bucks, you got a character, a vehicle, a bunch of groovy accessories, and a colorful cardboard land to drive 'em around on. Is it any wonder these little yarn-haired creatures were my favorite childhood toys?
And, yes, I still have them all. I let my kids play with them once, and only under my strict supervision. They have LEGO; they should leave my toys alone.
If you want me, I'll be under the dining room table, driving Miss Tickle Pinkle in her Bugabout car.
My mom must have read this to me 4 dozen times as a little girl. I read it to my son and now to my granddaughters. It’s a fun, silly, brightly illustrated book.