Sending your child to college is expensive, and tuition is only the beginning. A student at a four-year college shells out, on average, well over $9,000 for day-to-day expenses while on campus—and that doesn't include pricey necessities such as computers and cell phones, quasi-necessities such as televisions and DVD players, and the cost of participating in such college rituals as summer in Europe and spring break in South Beach or Cancun. Some of this is paid for by summer and term-time jobs, and some by credit cards: by sophomore year more than seven out of ten students have at least one card, and by senior year students carry an average of $2,864 in debt spread over five cards. But much of it, inevitably, is paid for by parents, roughly half of whom buy their child's computer (average price: $1,316), and 62 percent of whom send allowance money from home. The average allowance is $236 a month—or about $7,500 over four years.

Sources: Lifestyle and Media Survey, Computing and the Internet Survey, Student Monitor; "Undergraduate Students and Credit Cards in 2004," Nellie Mae.