Being married is really no obstacle to getting grants for school. In fact, most federal grants work off of income level, not marital status, so being married presents little challenge even for traditional avenues of funding. Of course, being married means that you probably have other special considerations that take up your time, so it's important to make sure you meet all the attendance requirements and any other special considerations that may come with being a grant recipient. Some grants even allow exemptions from some requirements for married students.
The Federal Pell Grant is the standard student grant program, and is not limited to unmarried students. The Pell Grant is awarded according to income, so if only one of you works, or if your combined income is below $50,000, you'll be able to apply.
Many grant programs, both federal and private, are offered to students with minority status. This includes African American, Native American, Latin American, Inuit, and other minorities. Most of these grants are concerned with your nation of origin as opposed to your marital status, so being married should not be an obstacle to your application being approved.
According to College Scholarships, many subject-specific grants are designed to draw students to study a particular major. These grants are most often merit-based, and will evaluate your GPA or other accomplishments in the field, and are not limited at all by marital status. College Scholarships also points out that many minority grants can also be for specific subjects, so if you find you qualify for minority grants, be sure to see if you also qualify for one in your field of interest.
Adult Learning Grants
Many married students are over the average age for college students. The truth is that the American college landscape is just as diverse as the rest of the population when it comes to age, and since some grants are only for older adult students, this may work to your advantage. Adult learning grants may be offered by your particular school. A few federal grants, like the Federal Supplemental Education Opportunity Grant, are just for adult learners. Married women can also check outside sources of assistance like the The Janette Rankin Foundation.
Returning Student Grants
Perhaps you started college once, but quit and decided to get married, but now you'd like to finish up. There are many grants available for just this kind of situation, and the getting married part won't affect your eligibility. For example, the Altrusa Grant Fund or the Alma Baron Second Chance for Women Grant are both for women who have previously attended college and now wish to return. Once again, these are not based on marital status, so married women may apply provided they meet the other requirements of the grant.