The answers lies ultimately in what's the biggest pull for the student.

Have they validated their business idea from by testing their product (or service) in the market and received feedback that there is demand for this product (or service).

The validation can be done alongside their studies by planning out their time each week and allocating time towards both their studies and testing the business idea. This will mean sacrificing other commitments (social or otherwise),which comes back to what the biggest pull is for the student.

If they are committed then they can study and start the business at the same time by being disciplined. If the business takes of to such an extent that the opportunity of growing and scaling the business to profitability is greater in the long run than finishing their studies then that is a decision only they can make in light of the information infront of them.

If the business has lesser success and enables them to finish their studies in the meantime before fully committing to the business then this is another decision that only they can make in light of the information infront of them.

Education is important and so is the concept of nurturing creativity and taking calculated risks. Evaluating the scenario comes down to opportunity management and deciding on the option that is the best fit for the student once a full assessment has been made of the options.

Also bear in mind that just because the student might quit their education right now to pursue the greater business opportunity (once their use case and product/service has been proven) doesn't mean that they cannot return to their studies at a later stage as and when they decide.

Wish them all the best and if they want to talk things through further, I'd be happy to help.