Hi.,
Im an american living and teaching English here in Mexico and unless you are a private institution, thats a high price your charging, remember we are living in a third world country and its rare to see people spend alot on teachers, clothes, jewelery, even shoes are like no way 100 pesos, but if living in a rich area 100 pesos seems to be fair.

I usually started charging like 50 then none came, then I lowered it to 30 and thank the lord i had people come in today....

So dont give up just move around till you feel comfortable with what you´re charging....

See ya Around.,
love,

Rosie