He wasn't the only one, though. A friend of a friend in the other class had the same idea.
"They were saying stuff like 'Yours is going to be nothing like his. His is going to be awesome. That's super hard to make,'" the 11-year-old Mercado said.
It was, don't get Mercado wrong. But he certainly blew away the competition.
"When I saw his, his was just construction paper in a circle with pictures," Mercado said. "His had sand all over and it was just a mess."
For the record, Mercado chose felt instead of sand for his model. But that's the least impressive aspect of his replica of the downtown landmark.
PVC piping takes center stage in Mercado's model, providing the sturdy outside structure. For the brick façade, he shrewdly cut pieces of cardboard, even constructing the side offices near Gate A.
And how about the trademark toothbrush lights? Empty gum capsules, of course.
Mercado certainly had a keen eye for innovation when constructing the model. At the start, though, it was a bit of a struggle.
"We were just trying to figure out how we were going to do this," Mercado's father, Rafael, said.
Before they started building, the Mercados did their homework. Luckily, Gabriel found a book at the local library that showed the stadium formerly known as Jacobs Field being built step by step.
The book helped, but the tireless work is what got Mercado a 104 percent.
When his friends were outside enjoying their free time after school, Mercado had to say a quick hello and go straight home. He had work to do.
"Sometimes I wanted to go outside and play, but I couldn't because I had to do this," Mercado said. "It paid off, though. My mom said, 'Hard work pays off.'"
For roughly three to five hours a night, Gabriel and Rafael worked tirelessly on the model, only taking time off to do a little more research.
"We had to watch the games to see what the field looked like," Rafael said with a laugh.
While Gabriel and Rafael did most of the dirty work, Mom was there to help with the finishing touches. Why make such good looking seats but have no one sitting in them?
After a couple Google searches, Progressive Field was sold out.
The only thing left to do was show it off to his class and the competition in the other class. To top it off -- and what convinced Mrs. Kaminski to do a little funny math in calculating his grade -- Mercado showed up to his presentation in a Tribe shirt with a Jim Thome bobblehead doll in his hand.
"When I saw my friend afterward," Mercado said, "all he said was, 'Yours crushes his.'"