I have several favorites:

First and favorite childhood model ship kit: Lindberg's LST (included gray thread for stringing railing between separate plastic stanchions and recently re-issued with an excellent decal sheet.)

Model aircraft: Monogram TBF Avenger (amazing wing fold engineering with retractable landing gear, dropping torpedo, and other working features.)

Other kits: Revell horse drawn fire fighter rigs such as chemical wagon, hose wagon, steam pumper. (Included figures of firemen, dalmation dog, and horses plus black vinyl strips for rigging reins to horses' bitts.)

Revell Highway Pioneers automobiles such as early Renault Limousine/cab and many others.

I even built a number of Revell HO scale model railroad building kits which were vastly superior to anything else around at that time.

Model building was highly educational and inspirational to me. I learned so much about history, engineering, and science while spending time at my work table. The designers and makers of these wonderful kits worked wonders with the youth of that time. They turned a semi-disciplined young rabble into the skilled men and women who took Americans to the moon, built the first jet airliners, and harnessed the great forces of nature to do useful work for all mankind.