This booklet is designed for both families and educators because the work of encouraging girls in math begins at birth and continues throughout the school years. Cooperative interaction must be provided in order to equip girls with the best chance possible to succeed at mathematics. This booklet provides information about the harmful and lasting effects on girls and boys of gender-role stereotyping. It helps administrators, teachers, and families as they develop ways to reduce gender-role stereotyping and encourage K-12 girls in math. The booklet also offers educators and families the most current strategies that work to encourage both girls and boys in math. Mathematics instruction must seek to engage rather than exclude girls, provide more female math role models for girls to emulate, and boost girls' confidence in their ability to succeed at math. This booklet suggests strategies and activities to promote equitable math for girls but benefit all students. Strategies include how best to build math confidence, making math careers relevant, using creative teaching strategies, providing positive female role models for girls and boys, improving test-taking skills, and increasing computer access for girls. (AIM)