Equivalent fractions are different fractions that represent the same value or amount. They have different numerators and denominators but have equal values when simplified.
Visual models provide a concrete representation of fractions, making it easier for students to understand the concept of equivalence. By shading or partitioning models, students can visually see how different fractions can represent the same whole.
Considering the size of parts is crucial in determining equivalence because even though two fractions may have different numerators and denominators, they can still be equal if their parts are of the same size or area.