DORCHESTER, Mass. (WHDH) -- A Dorchester school has gone Gaga. The principal showed up at school in a limousine, dressed as the pop idol.

It's not everyday a school principal dresses up like a pop idol, but when you're on the losing side of a bet you do what you have to do. And what Justin Vernon, Principal of Dorchester's Roger Clapp School had to do was impersonate Lady Gaga.

“I think I make for a pretty good Lady Gaga, what do you think?” Vernon asked his students.

And the second part of the bet was quite imaginative; Principal Vernon had to milk a cow.

“I think he really made a fool out of himself – in a good way,” said Margaret, a student.

Earlier in the year, Vernon challenged his K through 5 students to read 10,000 books -- and he promised if they did, he would do whatever they wished.

“Of course they wanted to yell out the most ridiculous thing possible. So milking a cow came out, dressing like Lady Gaga, there were other options that came out but this is the one that stuck,” said Vernon.

“My favorite part is when he milked the cow,” said Fiona, a student.

Of course, his students read all the books and then some. But being from the city, the thing many of the kids couldn't believe was the part about the cow.

“I thought he was going to dress up like Lady Gaga, but I didn’t' think they would get an actual cow,” said Mark, a student.

“I think they were still a little bit uncertain even today, some students asked, ‘Is it going to be a real cow?’ ‘Yes, it's going to be a real cow,’” said Christine Valenti, fifth grade teacher.

The cow came from Richardson’s Creamery, and some of the books were donated by Barry, formerly of Jordan’s Furniture. Many parents say this is one bet that paid off.

“I mean, my daughters reading went through the charts because of it,” said Theresa Davis, a parent.