As far as I know there's no Dental Schools that will do dental implants for free but you can usually get the dental implants done cheaper at a dental school.
The cost of a dental implant per tooth at a dental school is around $900.00 while at a regular dentist that same dental implant per tooth could cost as high as $1,700.00
So you would save $800.00 per tooth if you were to pay a dental school to do the dental implants.
Check around and ask your dental school or dentists if they know of any programs that can help you cover the cost of the dental implants.
There have been some places that were helping people pay for the dental implants to be done but it doesn't exist in all locations and you have to qualify for the free or low cost dental implants or other dental procedures.