Got pie?

In answer to Wednesday’s puzzler

It’s a “pi day” shirt. Every March 14th (3.14) the secondary schools that my boys have attended celebrate “pi day” — they get extra credit if they bring in round desserts: pie, cookies, etc. At their current high school, someone designs a shirt which they sell in advance to be worn that special day. The mathematical sentence reads: “i 8 sum pi” and on the back there is a cartoon figure of the math department head eating pie and saying, “I ate some pie!”

Congratulations to suburbancorrespondent and Thom — both of whom clearly surpass me in mathematics.