My wife and I had a disagreement recently about the ethical duties of a teacher. I teach fourth-graders and maintain that if a student mispronounces a word, it is my sacred duty to correct the student. It's the dictionary or the highway as far as I'm concerned. My wife says that regional accents (i.e., Boston, Deep South, etc.) should be left uncorrected. Who's right? -- Michael Leavenworth, San Diego

Whether sacred or profane, you are not Henry Higgins. You need not eradicate every flinty New England consonant or honey-toned Mississippi vowel. You should not strive to make your students speak like network news anchors. It is when a student deviates radically from the dictionary's description -- "libary," "eye-talian" -- that you must act. In such a case, you have an obligation both to treat your students with respect and to teach them standard usage, something you should explain from the get-go: No knock on how kids in your neighborhood pronounce things, but in class we must master the conventions of the larger world.

Your object is not to compel your students to assimilate into the dominant culture but to equip them with the knowledge to excel in it. While ours is a living language, in flux and rich with regional variations, some of which have connotations of race and class, were your students to use "nucular" in a job interview a decade hence, this would be regarded not as a charming colloquialism but a mark of ignorance. (Although apparently not as a bar to high office.)

But do not pester them about this on the playground. Another lesson to impart is that we use different sorts of language in different situations. Among our pals, we speak casually; we speak more formally to adults; and we would speak more formally still when introducing the queen or the pope to the ghost of Miss Helen Hayes, first lady of the American theater, even in Boston or the Deep South.

After my niece's first birthday party, her parents sent videos and I uploaded them to YouTube for family members to view. My sister-in-law sent me a stern note saying that unless images of my niece are accessible only to people approved by her and my brother, I may not post them. YouTube lets you restrict access, so I complied, but isn't her request overprotective and unfair? -- David, Los Angeles

The only videos more tedious than other people's vacations are videos of other people's babies. (I cower at the prospect of vacationing-baby videos.) Does your sister-in-law really imagine a popular clamor for the newest niece pics? But while her ideas about privacy and child-rearing differ from yours, so be it. That is a mother's prerogative. Overprotective, perhaps, but not unfair: her child, her rules.

In fact, her policy doesn't seem particularly extreme. She simply declines to have her family album published publicly, i.e., posted online. If she applied this restriction not to YouTube but to Entertainment Weekly, nobody would bat an eye. Perhaps she senses, with a mother's intuition, that hers is a very private baby.

This conflict could prove more vexing when it comes to videos that include both you and your niece. May you not document your own life? Alas, here too the mother's wishes prevail.

But her policy is easily accommodated. As you suggest, you can limit access to approved visitors at a Web site or, more traditionally, disguise your niece's identity by printing the customary black bar across her eyes, lending her an air of criminality, quite advanced for a child her age.