it occurred to Heinlein that he could earn money and reach a wider audience with a juvenile novel for boys. He conceived The Young Atomic Engineers and the Conquest of the Moon as a successor to the Horatio Alger and Tom Swift books that he had loved growing up, with an emphasis on the values of hard work and education, and he set certain rules for himself: “Never write down to them. Do not simplify the vocabulary nor the intellectual concepts. . . . No real love interest and female characters should be only walk-ons.”
