Klein, who grew up in public housing, could recall nothing more in the way of carrots and sticks than an allowance raise or a grounding for one of his bad report cards. His interest in succeeding was quite conventional.
"I wanted my parents' approval," Klein said. "I found education interesting and exciting and I engaged it in those terms. I thought education would create opportunities my family didn't have."
My father said if you want to grow up and not live in public housing, pay attention in school," he said.
The crucial if amorphous role homes play in whether a child succeeds is why Johnson thinks the chancellor should come to grips with the limits of what schools can do.
Other critics of the new program, like Sol Stern, a senior fellow at the Manhattan Institute, think Klein should put the incentives into college funds, saying instant cash undermines the idea of learning for its own sake.
Another parent, Joan Rose Palacios, whose daughter Olivia is a fourth grader in Queens, wondered: "What happens when the money dries up? You pull a carrot away, do they stop working?"
But, she added, she is keeping an open mind because she feels that schools in poor neighborhoods need more aid.
The pilot, devised by Roland Fryer, a 30-year-old Harvard economist who has studied racial inequality in schools, is part of a wider program by New York Mayor Michael Bloomberg's administration that will offer cash to adults for keeping a job, maintaining health insurance, attending teacher conferences and getting children to show up at school.
Laura Rawlings, an economist for the World Bank, which finances US$1.2 billion worth of incentive programs in 12 countries like Mexico, says such programs have raised school attendance.
The programs can be favorably seen as a form of income maintenance that replaces pure entitlements by requiring parents to commit to behaviors society prefers. But the Mexican program does not reward children for passing tests. And it may be hard to explain to children, sensitive to any unfairness, why one child is getting money while another with better grades is not.