Short answer: Aluminum is considered "paramagnetic." Most laymen would consider that to mean "non-magnetic."
Longer answer (and greatly simplifying): Materials fall into three categories, dependent upon their relative permeability (called 'Ur' in this post). Almost all materials have a relative permeability which is very, very close to the relative permeability of free space --> Ur = 1. The classification is as follows:
Diamagnetic: Ur is VERY close to 1, but slightly less than 1 (e.g., Ur = 0.99997).
Paramagnetic: Ur is VERY close to 1, but slightly more than 1 (e.g., Ur = 1.00003).
Ferromagnetic: Ur can be orders of magnitude greater than 1 (e.g., Ur = 7283.5).
~ALL~ materials have a diamagnetic effect. This is a small magnetic field, which is only present if another magnetic field is induced on the material, and serves to OPPOSE the induced field. If no other effect swamps out this effect, then the material is considered diamagnetic. Some examples of diamagnetic materials are: bismuth, copper, lead, mercury, silver, gold, and diamond.
Some materials have a paramagnetic effect which overcomes the diamagnetic effect. This is a small magnetic field, which is only present if another magnetic field is induced on the material, and serves to STRENGTHEN the induced field. Paramagnetism (unlike diamagnetism) is temperature dependent, being stronger at lower temperatures. A material which has this, but not ferromagnetism, is considered paramagnetic. Examples of paramagnetic materials are: aluminum; magnesium; tungsten; and titanium.
Ferromagnetic materials can have their own magnetic field, independent of an applied magnetic field. In addition, they can have very large relative permeabilities. Examples of ferromaagnetic materials are: iron; nickel; and cobalt. When ferromagnetic materials are heated above their "curie temperature," they lose their ferromagnetic properties and become paramagnetic.
Then there are ferrimagnetic (used in ferrite beads) and anti-ferromagnetic materials, which we won't get into.
So, the big breakpoint is between ferromagnetic materials and anything else. It does not matter much to most laymen whether Ur is 0.99999 (diamagnetic) or 1.00001 (paramagnetic). Both types of materials have a Ur of almost exactly 1. They do not interrupt or divert magnetic lines of force. Unless you have a very, VERY highly concentrated magnetic force (as in an MRI exam), there is no observable effect on these materials. The layman considers them "non-magnetic."
Magneto: Something to think about is that most metals do conduct electricity very well. Inducing a circular current in a piece of metal would make that piece produce its own magnetic field (electromagnetism). That field could then be acted upon by external forces to manipulate the object.