In three months, technology entrepreneur Hadi Partovi raised $10 million from the likes of Bill Gates, Google and Mark Zuckerberg for Code.org, a non-profit aimed at expanding computer science education in the United States. Now it’s time to start spending it. On Monday, Code.org will kick off its most high-profile event to date, Hour of Code. More than 30,000 schools–about 70% of them in the U.S.–will dedicate at least one hour this week to teaching students about computer programming. Several technology leaders and other bold-faced names have already contributed video messages and resources for the roughly $1 million effort, including President Barack Obama, House Majority Leader Eric Cantor and the pop star Shakira. But Partovi, an investor and former Microsoft executive, sees an uphill battle ahead.