Ella has two major phobias in life: spiders and mathematics. She firmly believes that anything with more than four legs should not exist. She also believes the world would be a better place without word problems or long division. That being said, she's fascinated by science. So when her class finds a dead opossum in the playing field one morning, she's intrigued by rigor mortis and how long it will take for the opossum to unstiffen. Science is so much more interesting than math.
Later that day, Ella is certain she must have heard wrong when her teacher announces that there will be no more math tests for the rest of the year. And she isn't wrong—it is too good to be true. Her teacher explains that instead, the class will be having its first ever math fair. Ella's group is assigned the topic of time conversions, something Ella's been struggling with for a while. This is hardly Ella's idea of fun. But Ella's mom is quick to point out that math and science aren't so very different—she suggests that Ella imagine she's doing a science experiment instead of a math project. With a little imagination and some inspiration from their friend the opossum (now named Morty, short for rigor mortis), Ella and her group come up with a project that gets them excited about math—and they might even have a chance to win at the fair!