STEM Gateways Act - Directs the Secretary of Education to award competitive grants to eligible entities for science, technology, engineering, and mathematics (STEM) elementary and secondary school programs for women and girls, underrepresented minorities, and individuals from all economic backgrounds.

Requires those programs to be directed toward at least one of the following goals:

• encouraging the interest of elementary and secondary school students in the STEM fields;
• motivating the engagement of those students in the STEM fields by providing them with relevant hands-on learning opportunities;
• supporting classroom success in the STEM disciplines by elementary and secondary school students;
• supporting STEM workforce training and career preparation for secondary school students; and
• improving the access of secondary school students to STEM career and continuing education opportunities.

Defines an "eligible entity" as: (1) a local educational agency (LEA); (2) an educational service agency serving more than one LEA; (3) a consortium of LEAs; (4) a nonprofit organization that works with elementary schools, secondary schools, or institutions of higher education and has shown a commitment to achieving the goals listed above; or (5) a community college working in partnership with secondary schools to create dual enrollment, credit transfer, or accelerated postsecondary credentialing opportunities.