Oo or Wuh? Disparity When Trying to Teach Letter Names

Today in a workshop, I was told not to teach the letter W as /wuh/, but as /oo/, like I'm puckering up my lips to blow air through them.

For many years, I've had to battle UN-teaching children how not to pronounce certain letter names, and to replace those sounds with correct ones. For instance, the letter P is not /puh/, and G is not /guh/. Otherwise, when a student faces the word PIG, they're pronouncing it Puh-ih-guh, and can't figure out the word from that blend.

To be honest, I can't remember what my original reading teacher did when I was in elementary school, back in the Dark Ages. However, I do recall the horror I felt when I was taking reading classes in college, and my professor, with her thick Southern drawl, proceeded to make us repeat the number Four as "fow-ah".

Every year at least a goodly handful of my class have been taught to pronounce certain letters the wrong way. But B is not /buh/, C is not /cuh/, and D is not /duh/, as much as L is not /luh/, M is not /muh/, and so forth.

I wish there was an easy solution. Otherwise, I wouldn't have to worry about spending precious time correcting reading mistakes.  Which makes me wonder...is /oo/ the new W? Or have I somehow missed the memo?