Investing in 21st Century Workforce Partnerships Act This bill requires the Department of Education (ED) to establish a career pathways innovation grant program to award grants to address the specialized skill needs of business and industry by carrying out study or career pathways programs, featuring school partnerships, that support career pathways in high school or career exploration in the middle grades. The bill amends the Higher Education Act of 1965 to direct ED to award grants for partnerships—between certain educational entities and employers—that provide educational or career training programs leading to recognized postsecondary credentials.