Girls x Math chapters include both high school mentors and third and fourth grade students, all of whom identify as girls. Each mentor is paired with a group of 2-3 elementary school students to work on fun projects, problems, and games. Chapters may choose whether they would like to keep these groups the same each session or if they would prefer to mix up the groups.

Girls x Math provides its chapters with ten free activities, each of which take 45 to 60 minutes to complete. Each activity explores a different area of math and elaborates on skills the students learn at school. Rather than tutoring the students, Girls x Math offers real world applications to help nurture a love of math by solving open-ended, contextual math problems. These lessons, and the opportunity to work in small groups rather than one-on-one with a mentor, encourage collaborative problem-solving skills and promote a supportive math community. Girls x Math activities highlight a variety of topics including multiplication and addition, area and perimeter, irrational numbers, permutations, latin squares, geometry, fractions, and applications of math in art.

Along with each activity, Girls x Math provides extensive lesson plans for all mentors. These lesson plans include discussion points, ways of explaining more difficult topics, and detailed instructions for teaching each activity. The lesson plans attempt to answer any questions a mentor may have in order to ensure that mentors will be confident in their teaching abilities.