Here is a math problem: X = the number of Grandview Heights Schools students who earned a perfect score in at least one test in the 2018-19 Continental Math League program.

In this case, X = 13.

Now, here's a vocabulary word: indefectible, meaning flawless or perfect, as in, "Five Grandview students' command of language proved indefectible when it comes to their results in a WordMasters Challenge meet."

In plain English: Thirteen Grandview students from Stevenson Elementary School and Edison Intermediate/Larson Middle School answered all six questions correctly on a Continental Math League test last school year, and five Stevenson and Edison/Larson students achieved perfection by answering all 20 questions correctly on a WordMasters Challenge.

Grandview students who scored a perfect 20 on one of the three WordMasters tests offered this year are Mira Bondy, third grade; Owen Bentley, fourth grade; Penny Debelak and Emina Osborne, fifth grade; and Vivi Chute, seventh grade.

Students who earned perfect scores on the Continental Math League test are third-graders Millie Chrstos, Benji Gusty, Luke Lee and Jackson Mohr; fifth-graders Cooper Bauer, Beck Joubert, Sophia Patterson, Landon Roberts, Collin Sauer, Luke Stanley and Kinny Wilson; and sixth-graders Mario Bondy and Ben Carini.

More than 150,000 students nationwide in grades 3-8 participate in WordMasters, and 40,000 students in grades 3-7 participate in the Continental Math League.

"It's quite an accomplishment to earn a perfect score" in either program, said Joan Grundey.

Grundey and another Grandview Heights Schools enrichment teacher, Jannel Kumar, teach the Extended Learning Class offered to students in grades 3-7.

The class focuses on skills such as critical and creative thinking and problem solving, Grundey said.

The sessions include time to work on academic challenges and logic problems along with preparing for the WordMasters and Continental Math League, Grundey said.

Three WordMasters competitions are held each school year and five math-league tests are given.

Students qualify for enrollment in the Extended Learning Class based on their results on the InView Test, a standardized assessment that measures students' cognitive abilities, Grundey said.

About 60 students in grades 3-7 participated in the class last school year, she said.

"I'd describe the students in the class as being very curious and self-motivated," Grundey said. "They like to think and learn outside of the box.

"These are students who aren't just satisfied learning that some number systems have zeros but earlier systems did not. They'll want to explore and learn why some number systems did not have zero," she said.

Depending on the grade levels, students participate in the Extended Learning Class two to five days each week, Grundey said.

"It's a chance for the students to work with their intellectual peers and with other students who are interested in some of the same things," she said. "It helps them become more self-aware of where their talents lie and their own capabilities."

Students come to class not only ready to learn but also ready to help set the agenda, Grundey said.

"We had one student this year who asked if she could bring in a couple guppies," she said. "That led to more students bringing in guppies, and then bringing in some snails. We went from having a fishbowl in our classroom to three aquariums. That was all student-driven."

For Mira and Mario Bondy, participating in the Extended Learning Class is a family affair.

Mario will enter his fifth and final year in the class next school year as a seventh-grader, and Mira just completed her first year as a third-grader.

"There's a little bit of competition between us," Mira said.

"I think she wants to do a little better than I did when I was at her grade level," Mario said.

Family ties overcome competition, though, he said.

"If one of us does well, we're really happy for each other." Mario said. "We're pulling for each other."

Mira was one of 15 students in her grade level nationwide who earned a perfect WordMasters score, district officials said.

Both Mira and Mario said they enjoy both the vocabulary and math challenges, but they have their own preferences.

"I prefer math because I like that you can always find a direct answer to the problem," Mario said. "It's cut and dried. There's a right answer and the challenge is to figure out that answer. I like the certainty of it."

Mira gets a greater charge out of WordMasters in part because she likes the ambiguity of language

The questions on WordMasters can be tricky because multiple words that are given as potential answers in the analogy questions can seem to have similar meanings, she said.

"I love synonyms because there is more than one right answer," Mira said. "One day, I was writing a letter (for a class project) and my teacher suggested I try to come up with a different word to use instead of fun. I ended up coming up with the word beguiling, which I just love the sound of. But there were so many other choices I could have made."

At the start of each school year, the siblings write on a small chalkboard at home what they want to be when they grow up.

"When I was in kindergarten, I wanted to be a zookeeper," Mira said.

"This year, I wanted to be an artist. I might become a writer. I love to read whenever I can, and sometimes I like to come up with stories on my own in my head."

"She's a born storyteller," Mario said.

In his younger days, Mario wanted to be a chef.

Now his ideal professions are a marine biologist or a litigator.

Math is involved in almost any career path one might choose, Mario said.

"People might wonder why math is important, but they don't realize how we all use it every day," he said. "Even a chef uses it to measure ingredients."