Riddle

I posted this riddle on my board for students to solve:

I come in different shapes and sizes.
Part of me are curves, others are straight.
You can put me anywhere you like, but there is only one place that I truly fit.
What am I?

Student:  Mrs. A, I know the answer to the riddle.
Me:  Okay...
Student:  The answer is: a woman.  She has curves and only fits in one place...the kitchen.
(Student waits for my reaction)
(I start laughing)
(Student, relieved, is laughing with me)
Me:  The correct answer is puzzle piece.
Student:  I like my answer better.