Lego's much-cheered female-scientist minifig kit from 2014 and Women of NASA set from 2017 aren't just aberrations. They're a sign of the times that tie in with a major change in the way US children see scientists.  

A team of researchers from Northwestern University pored over five decades of "Draw-A-Scientist" studies that asked children to sketch what they thought a scientist looked like. The researchers found kids in recent years are depicting female scientists more than ever before.

The Northwestern team says this finding is "consistent with more women becoming scientists and children's media depicting more female scientists on television shows, magazines and other media."

The 78 Draw-A-Scientist studies started in 1966 and included over 20,000 children over the years ranging from kindergarten students through high schoolers. 

The first study, conducted between 1966 and 1977, involved 5,000 kids and resulted in less than 1 percent of the children drawing an image resembling a woman. A typical drawing showed a man in a lab coat with glasses and facial hair.

Later studies dating to 1985 through 2016 show that 28 percent of the kids drew a female scientist, with girls drawing female scientists more often than the boys.

"Given these results, girls today may develop interests in science more freely than before because children's stereotypes of scientists have become less masculine over time," said study co-author Alice Eagly, a Northwestern psychology professor. 

The study, published Tuesday in the journal Child Development, also looked at child development and the age at which kids form stereotypes about scientists. The team found kids did not associate science with men until around age 5, with the tendency to draw male scientists increasing through elementary and middle school. 

Co-author David Uttal, also a psychology professor, has a suggestion for parents and educators looking to combat scientist stereotypes. 

"To build on cultural changes," he says, "teachers and parents should present children with multiple examples of female and male scientists across many contexts such as science courses, television shows and informal conversations." 

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