Rapid Fire Questions for people living in Japan

(I tried asking this in r/AskaJapanese but the mods removed it even though this isn't really about how to use the language, so I'm hoping some Japanese natives can help me out.)

Hello, everyone! I'm a linguist who specialises in Japanese. Naturally, language, culture and society are intimately tied together, but I have not lived in Japan (visited, though). I am hoping that some people who do experience regular life there can answer some quick questions I have (based on sociological literature from the 80's to the present day).

When you answer, please let me know if you are Japanese or a resident of Japan (if your flair isn't clear). Thank you!

  1. Do young boys learn to use 俺 at school? (That is to say, it's not taught at home.)
  2. Does the ending particle わ sound effeminate, or have impressions changed?
  3. Do bosses call their subordinates (even females) くん? (I've always got the sense this is old fashioned)
  4. Do bosses still give speeches at weddings? If not, does anybody who is not a relative of the bride and groom customarily give a speech?

by alpolvovolvere