Formula conversion to mass is a nice tool and this will do the job quickly, allowing students to calculate formula masses for compounds. As a teaching tool, this is not as useful, except to check ones answers.
A potential way to improve it as a teaching tool would be to 'expand' the formula during the calculation. C6H6 would become:
1 mole of C6H6 contains
6 moles of C at 12g/mol = 72 g C
6 moles of H at 1 g/mol = 6 g H
Total mass (formula mass) = 78 g C6H6