When 2 fractions refer to the same whole explain why the fraction with a lesser denominator has larger pieces than the fraction with a greater denominator

The denominator tells how many pieces the whole is broken into. So a denominator of two tells you that the whole is broken into two pieces. A denominator with 8 tells you that the whole is broken into eight pieces. Think of a pie. if it is cut into two pieces that's two halves. if it is cut into 8 pieces then that is eighths.