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Ada is a Mission Guide from Pokémon Learning League. She assists students when they watch Mathematics lessons. She also makes a cameo in the Science Lesson, Scientific Method.
As the Learning League Lab's resident mathematician, Ada's very capable of solving problems when it comes to numbers. She's able to show how to solve any math problems that those who contact her come across. She's also very fashionable and has a penchant to talk about her shopping experiences if she goes onto that topic.
Naturally, Brock would sometimes try to flirt with her, as he usually did with any other woman, but just like nearly every other woman that Brock hits on, Ada's either flattered or just brushes it off.
It is revealed in the episode "Giving Back" that she also tutors kids in math in her spare time. She is also active in that she rides her bike and rock climbs.
Ada is portrayed as Hispanic, especially in later made episodes, where she interjects Spanish phrases such as "Hola".
Her name may have been derived from the word "Add". It may also be a reference to the famous mathematician and the world's first computer programmer, Ada Lovelace and the computing language named after her in the 1980s.