As stated above, can an F1 student elect to be treated as a resident alien for tax purposes? As in, can an F1 student choose to not exempt their days in the US under the substantial presence test?
While there is no formal election (that I know of; the "first year election" under Section 7701(b)(4) is not really applicable here), there seems to be an informal "election" availble.
The substantial presence test provides an exception for "exempt individuals" (a category which includes F1 students). Specifically, under the exception, the days of the year during which the NRA was an exempt individual do not count toward the SPT. The important point here is that, in order to be entitled to the exempt individual status, the NRA must affirmatively claim the exemption on IRS Form 8843. The IRS specifically states in its instructions and the form itself that if the NRA does not timely file Form 8843, he cannot exclude the days he was present in the U.S. as an exempt individual.
So it appears that the student can effectively elect to be treated as a resident alien by simply failing to file Form 8843. So I, too, learned something new today....