It is a qualifying "life event" only if the move to college is a permanent address change. If she will not be getting a new driver's license in the new state, she may not be considered a permanent resident.
She has little income and based on information in another thread, the new state is ND so a permanent move would place her into their expanded Medicaid program.
Someone suggested a catastrophic plan. For a temporary relocation it would need to be obtained in her current state of residency. Most Cat plans are single state so it's likely to be a network similar to the current family plan.
A person can have multiple health plans, one will be considered primary and other secondary.
This link is for California but should apply to other states as well. It appears to indicate that a person cannot have both student insurance and subsidies at the same time. The portion of the family plan premium allocated to the child would be eliminated from subsidy consideration but the subsidy for the parents would continue as
this link explains.
You may want to research the economics of switching to a PPO or Multi-State family plan with coverage in both states in 2016.