Mass
Mass explained in an easy to understand way:
Imagine you're packing a suitcase for a vacation, trying to decide how much you can fit inside. Just like you assess the contents of your suitcase to determine if it’s over the airline's weight limit, mass measures the amount of matter within an object. The weight of your packed suitcase represents its mass; every item you add is like adding more matter, increasing the suitcase's mass, just as each particle contributes to an object's total mass.
Practice Version
Mass: The amount of matter in an object. Mass. Mass is how much stuff is inside an object and doesn't change if the object moves to a different place.