"I'm a math teacher. Of course I have problems."

Price: $19 ($22 for 2XL and larger).

Pricing: $24 ($27 for 2XL & larger).

Available in regular men's, women's classic fit, and youth sizes.

Comes in Men's, Women's, and Youth sizes, and in Men's Long Sleeve.

Currently out of stock in Men's Small and Medium.

A few thousand digits of Pi, arranged so that you can read them in continuous order through the shirt, printed in the form of a Pi symbol. Available in Men's, Women's classic fit, and Youth sizes.

Available in regular men's and in women's Hanes classic fit.

Pricing: $20 and up.

Available in Men's and Women's sizes.

Pricing:

Men's: $20.

Women's soft, ringspun Hanes classic fit: $24.

Add $3 for 2XL and larger.

The Pi-Lingual t-shirt features geometric diagrams for area and circumference of a circle, and a wide variety of advanced formulae featuring Pi.

T-shirt is Black.

Pricing: $20 to $23.

BEST SELLER. Comes in Men's, Women's, and Youth sizes.

What do you get when you divide the circumference of an apple by twice its radius?

Apple Pi.

Add $3 for 2XL and larger.