Some students purchase student health insurance plans when they go to college. But some student health plans don't offer the Minimum Essential Coverage (MEC) that the Affordable Care Act required most people to have in order to avoid a tax penalty in 2018.
Starting January 1, 2019, there will no longer be a federal penalty for not having insurance coverage. That means if you do not have insurance from January - December 2019, you will not have a tax penalty.
If you aren't sure whether your student health plan is approved as MEC, ask your school.
You (and your dependents if you have them) won't be eligible for a special enrollment period (SEP) if you lose coverage under a plan that does not meet MEC standards. In other words, you won't be able to enroll in a parent's plan until the open enrollment period.