Emailing Coaches

I like copying on same email.  Take reasonable steps to make sure that they are both still active coaches with the program and specifically address any previous dialog to the coach you communicated with.  Also, be sure to take the time to research and spell out a few specific things about the school and program you are drawn to as well as list a few things about yourself that tells them why you would be a good fit.

This is assuming you are attaching a player video or link.

My son used both methods based on the situation i.e. if he already had dialog going with one coach or another, if he had been referred, or if he was exploring the situation essentially blindly. In cases where he emailed  multiple coaches separately he noted somewhere in the body of the message that he had also reached out to the other coach(es).

I recommended emailing the head coach, and cc:ing the assistant and recruiting coaches.  Seems effective thus far

Yes on including both coaches.  I think that it is a good idea to look over last year's results and compliment the coach(es) on the season, if appropriate.  For instance, winning the conference or improving the record by a significant margin.  Everyone appreciates a compliment and it shows them that the potential recruit is paying attention.  Easier to do during the season when the team may have just won or swept a series.