In a long line of ignorant things said over here at PPP, that's right up there. Nice work. Not only weren't the founding fathers Christian, many were avowedly non-Christian.
Here's a smattering of proof. If you want more, just ask. Or maybe read a little history.
"In every country and every age, the priest has been hostile to liberty. He is always in alliance with the despot ... they have perverted the purest religion ever preached to man into mystery and jargon, unintelligible to all mankind, and therefore the safer engine for their purpose." - Thomas Jefferson, to Horatio Spafford, March 17, 1814
"As I understand the Christian religion, it was, and is, a revelation. But how has it happened that millions of fables, tales, legends, have been blended with both Jewish and Christian revelation that have made them the most bloody religion that ever existed?" - John Adams, letter to F.A. Van der Kamp, Dec. 27, 1816
"I almost shudder at the thought of alluding to the most fatal example of the abuses of grief which the history of mankind has preserved--the Cross. Consider what calamities that engine of grief has produced!" - John Adams, letter to Thomas Jefferson
"Experience witnesseth that ecclesiastical establishments, instead of maintaining the purity and efficacy of religion, have had a contrary operation. During almost fifteen centuries has the legal establishment of Christianity been on trial. What has been its fruits? More or less, in all places, pride and indolence in the clergy; ignorance and servility in the laity; in both, superstition, bigotry and persecution." - James Madison, "A Memorial and Remonstrance", 1785
"Is uniformity attainable? Millions of innocent men, women and children, since the introduction of Christianity, have been burnt, tortured, fined, imprisoned; yet we have not advanced an inch towards uniformity. What has been the effect of coercion? To make one half the world fools, and the other half hypocrites. To support roguery and error all over the earth." - Thomas Jefferson, from "Notes on Virginia"
"[T]he government of the United States of America is not, in any sense, founded on the Christian religion;" United States Treaty (1796-1797)
"In the circle of my acquaintance (which has not been small), I have generally been denominated a Deist, the reality of which I never disputed, being conscious I am no Christian, except mere infant baptism make me one; and as to being a Deist, I know not, strictly speaking, whether I am one or not, for I have never read their writings; mine will therefore determine the matter; for I have not in the least disguised my sentiments, but have written freely without any conscious knowledge of prejudice for, or against any man, sectary or party whatever; but wish that good sense, truth and virtue may be promoted and flourish in the world, to the detection of delusion, superstition, and false religion; and therefore my errors in the succeeding treatise, which may be rationally pointed out, will be readily rescinded." Ethan Allen
"My parents had early given me religious impressions, and brought me through my childhood piously in the dissenting [puritan] way. But I was scarce 15 when, after doubting by turns of several points as I found them disputed in the different books I read, I began to doubt of Revelation it self. Some books against deism fell into my hands; they were said to be the substance of sermons preached at [Robert] Boyle’s lectures. It happened that they wrought an effect on me quite contrary to what was intended by them; for the arguments of the deists, which were quoted to be refuted, appeared to me much stronger than the refutations; in short, I soon became a thorough deist." Benjamin Franklin
"All national institutions of churches, whether Jewish, Christian, or Turkish, appear to me no other than human inventions, set up to terrify and enslave mankind, and monopolize power and profit." Thomas Paine
"Washington's religious belief was that of the enlightenment: deism. He practically never used the word ‘God,’ preferring the more impersonal word ‘Providence.’ How little he visualized Providence in personal form is shown by the fact that he interchangeably applied to that force all three possible pronouns: he, she, and it."James Thomas Flexner