The spouse may seek L-2 status and is employment-authorized incident to that status, so he could work in Colorado, though a driving job would need U.S. licensing. A nineteen-year-old at cégep can hold L-2 but cannot work and ages out at 21.
Separate the spouse's work permission from the child's clock
Hypothetical example: the operations director's husband drives a school-bus route for a transport contractor around Stoneham-et-Tewkesbury and their son is nineteen and in his second year of cégep. The husband's position is the easier one. As an L-2 spouse he is employment-authorized incident to status, which means he may take a job in Colorado without a separate work-permit application, though a commercial driving job would require a state commercial licence and medical certification of its own.
The son's position needs a calendar. L-2 children may study, so he could finish his program at a U.S. college, but he may not work, and his eligibility ends at his twenty-first birthday regardless of how much of the seven-year L-1A period remains.
If he plans to finish cégep in Québec first, decide who stays with him and whether the household moves in stages. Each person's file lists their own passport, relationship proof and intended activity.