I've sold lots of sets of color cubes, but I especially love these small look-alike sets  produced in West Germany for the WISC IQ test, which were used by the test taker to recreate increasingly complex designs shown by the test administrator within specified time limits.  These sets have become quite collectible, and no wonder--hard to beat a classic design object housed in a box with "The Psychological Corporation New York, NY" printed in silver on the top! I'm including with this one a small booklet that features a section of Block Designs to be recreated with the blocks, as well as a section of "Image Completion" problems with great graphics.

The WISC Test, which I believe continues to be used, is an IQ test administered to children between ages 6 and 16.  Developed by David Wechsler and individually administered, the test is organized into subtests relating to measuring verbal IQ, performance IQ, and full scale IQ.

Box measures 3 3/4" x 3 3/4" x 1 1/4". Cubes are 1 1/16" each side. Very good condition.