Just a quick note to let you know that Charlotte Taylor of Charlotte's Library has started a weekly roundup of posts about middle grade sci fi/fantasy book reviews and interviews with authors. You'll find that the review below is linked, but more important, I wanted you to be aware of this resource for future reference. Also, Charlotte often publishes lists introducing the newest books for children in sci fi/fantasy. I highly recommend her site for kids, parents, and teachers with an interest in the genre! Here's the link to today's roundup.
Art is "Erstaunlich," Margret Hofheinz-Doring, Strukturmalerei, 1964.