College Students with substantial need-based scholarships need to file returns?

Our college students are dependents (18 and 20 years old), who have NEVER filed tax returns, but they now receive a lot of need based aid reported on 1098-T forms, and other W-2 income. So, I am trying to determine if they need to file this year. Their income is as follows:

  1. Younger student: W-2 income of $7,000 from summer job; 1098-T Box 1 (QTRE) of $4,129 and Box 5 (Grants) of $9,817. So does that mean about $5,700 possible taxable grants plus $7,000 income means total is about $12,700 and under the filing requirement of $14,600? Am I doing this right?
  2. Older student: W-2 income of $6,700 from summer job; 1098-T Box 1 (QTRE) of $12,000 and Box 5 (Grants) of $30,100. So does that mean about $18,100 possible taxable grants plus $6,700 income means total is about $24,800 and must file since well over $14,600?                  

I don't know if I am doing this right and would appreciate some advice about this!

THANKS!