The spinning piece of foil has about a dozen variants including that of making a pen spin about, most all of it a matter of 5th grade science... at least, in my experience. HOWEVER, there are several version that have been marketed within the magician's market that are gimmicked in a variety of sometimes "clever" ways.
When I talk about PK/TK on stage and in my Psychic Development Classes I too state that it's nothing "super natural" (as I do with most all Psychic type things); my explanation taking into account a rare anomaly (about one in twenty) within the human physiology that is sometimes quite pronounced that results in a person exhibiting an exceptionally potent form of "static" or what medical researchers have coined "bio-electro-magnetic current" in that the phenomena brings about situations quite similar to magnets being set near a compass, most watches, electronics, magnetic storage devices, etc. Some of these individuals have such a powerful magnetic/electrical field around themselves that they must wear a grounding wire almost constantly so as to prevent shocking others or damaging electronic devices in their homes, cars, etc. This includes causing tools and other items that are of the appropriate material base, to become magnetic within relatively short time exposure (use) by them.
I believe I've mentioned this before, when I first came here and it is something Banachek and I have had a few discussions on over the years in that it does offer some sound plausibility to things that goes a bit beyond other energy field explanation like Chi or Reiki, etc.
Not to disclose things too much here, but I'd suggest those that buy into the whole PK thing, especially elementary demonstrations of this sort, learn a bit about working with neodymium Magnets and Kevlar thread strands (we're talking about fibers you can barely see under a magnifying lens that are outrageously strong) as well as Wooly Nylon...