By volunteering to teach ESL in prisons. Check out the recent CNN video about ESL classes in prisons.
According to an older article in the Christian Science Monitor and a 2005 article from ABC News, the US has a rather high incarceration rate. Surely there are reasons for and implications of this which are a bit beyond the scope of the TEFL Logue. But the point is, there are lots of people imprisoned in the US and some of them can benefit greatly from English as a Second Language training. Society can also benefit from this as there is a reduced recidivism rate, according to the Windham School District, which was created solely to cover education in the vast system of prisons in the state of Texas.
Many people are already aware of more typical avenues for volunteering English language instructions skills such as with immigrants or refugees, such as programs which can be found at Idealist.org. Fewer people are aware of the possibility of volunteering in prisons.
DOWNLOAD OUR TRAVEL GUIDES
One existing program which connects volunteers with prisons is the Prison Dharma Network, though their focus appears to be on teaching contemplative methods rather than ESL. You can find additional information about the Volunteer Services Program at the Texas prison system here.
Stay tuned for more information about volunteering your English language teaching skills in prisons and elsewhere.