Since "outside influences" are a challenge to tznius, Rabbi Pesach Eliyahu Falk writes in his sefer Oz veHadar Levushah (pg 132) that one should not bring in secular newspapers, or chas veshalom a television. But this also means having plenty of "kosher" reading material available. This means "kashering" the material as needed. Thus, he suggests that in the case of a children's encyclopedia, a Jewish parent should take a black marker and black out any text which reveals that scientists believe the earth to be greater than 6000 years old.
This makes me sad.
And it is not just that I disagree that claiming the universe is older than 6000 years is kefirah. (I know they have resolutions, convincing or not-so-convincing.) Rather, it is the idea that one must be protected from the knowledge that scientists maintain something different from Chazal. And that censoring such information reinforces a closed-minded and ignorant mindset, in both those doing the censoring and those from whom this information is concealed.