A few articles I need to re-write but they're not terribly irrelevant:
Make Your Site Sell | WebsiteMaven Search Engine Basics | WebsiteMaven
Don't expect to be at the very top of Google search results for piano lessons but you can try to achieve "local dominance" for that search term.
I would make sure her web site has the words piano, lessons, Plainfield, IL interdispersed through the opening words. Check out my chuch website at
Central Baptist Church, Okinawa, Japan to get an idea on how I use the terms Okinawa, Baptist, Christian, and Church all throughout the text so that it reads like normal text but it also reads well.
Secondly, I recommend your wife start adding lots of free content. Maybe guides on how to buy pianos or what music is good. Regular articles and maybe even a blog on piano lessons will provide more content compared to others that are slapping up a basic site. You might want to build her site in Wordpress that is great now as a basic website but allows blogging as well.
Just a few thoughts.