As fundraising has become a key component of American public school music educators' professional responsibilities, in many places, parent organizations have taken an increasingly outsized role in raising private funds to supplement public school music budgets. The purpose of this study was to understand the finances of public school music parents' associations and music booster groups and to understand the relation between the socioeconomic status of school communities and the amount of money raised by their local music booster groups. Using Internal Revenue Service (IRS) fiscal 2015 data for 5,575 music booster groups throughout the United States, we found evidence that, collectively, music booster groups raised at least $215 million in support of public school music education. At least four groups raised over $1,000,000; at least 31 raised over $500,000; and at least 723 raised over $100,000 each. We found that total booster revenues were significantly associated with local median household income. Each additional $1,000 of local median household income was associated with an additional $305 in revenue for booster groups filing IRS Form 990-EZ ("short form") and with an additional $1,637 in revenue for booster groups filing the full IRS Form 990.