A spouse in L-2 status is employment-authorized incident to status. Children in L-2 status may attend school but may not work, and they cease to qualify as dependants when they turn twenty-one.
Two different answers in the same household
It is worth stating the two rules separately, because families frequently merge them. The spouse's position is comparatively generous: employment authorization flows from L-2 status itself, so a spouse can take a job without waiting for a separate grant, though employers will still need documentation acceptable for employment verification and it is sensible to sort that out before a start date is promised. Children are in a different position entirely. They may enrol in school at any level, and they may not work at any age. The twenty-first birthday ends dependent eligibility, which for a family with a teenager can arrive in the middle of an assignment. A household with a child of seventeen or older should raise that date at the first consultation, because the alternatives available at nineteen are wider than the alternatives available at twenty and eleven months.
Hypothetical example: A Canadian dental-software company transfers its implementation specialist to Texas, where the specialist's spouse plans to seek local employment and their nineteen-year-old child plans to attend college. The family should treat those as two separate status questions. A qualifying L-2 spouse may work based on that status, subject to an employer's verification process; a child can study but is not allowed to work, and dependent eligibility ends at twenty-one. The first record to review is each family member's admission document and passport validity, not the principal's technical petition. Confusion commonly arises when a campus job or freelance project is treated as part of studying. Planning the child's independent education option early is more reliable than waiting for the birthday deadline or the principal's five-year L-1B limit.