Matter is anything that has mass and takes up space. So, in order to prove that air is matter, we need to prove that air has mass and takes up space. It's easier to prove that air takes up space, so let's do that part of the problem first.
Get a balloon and inflate the balloon with air. The balloon get larger as you put air into them. The only way that air could make them get larger is if air takes up space.
Also the balloon can be weight before air is added and after addition of the air. The weight will be much after adding air
Matter is the components with which a thing or an object is made of. Air, water, human body, Planets, stars etc. all are constituted by matters. They are composed of atoms.
Matter changes form whenever there is a change in the sequence of the atoms of that matter. Air is a light state of matter which is not visible with open eyes. It has gas particles which helps it to flow freely.
