District Treasurer? It is a very good EC, and if you show truly how you are NOT just a position holder and actually did major things w/ it then it can be a very good EC, but realize this;
It is NOT A HOOK.
There are HUNDREDS, if not a THOUSAND Key Club District Officers nationwide. Even being President of your State's Key Club is NOT a hook, since there are simply so many Key Club national-officers. For Key Club, personally, only once you get up to the International Trustee or International President level is it a 'hook'. (The tradition for Key Club usually is that the International President goes to Princeton, and for good reason, obviously. The recent Key Club international president, Grant Lin, scored 36 on his ACT...>_<).
But don't let that discourage you - its still 'noteworthy', and is good enough of an ec for the ivy league. I personally know any key club office requires a TON of work with all the constant paperwork and such, and I'm sure admission offices know so as well.