No one wants handouts because they are insulting and demeaning. Instead, the government should focus on fighting unemployment and poverty in the first place. No voters would consent to giving free money to poor high school students in exchange for simply attending classes. This is a backwards policy that would gain no support.
Students who are in the low-income bracket should not be paid to attend high school. Going to high school is a choice and not a right, so they should not be compensate for choosing to go. However, they should receive reduced lunches and subsidies to help offset transportation and supplies to help them complete high school.