The numbers are in: the Walton Family Foundation invested $157 million in grants for K-12 education reform in 2010, a $23 million increase over its 2009 total of $134 million, reports the Huffington Post. The 23-year-old foundation, created by Walmart Founder Sam Walton and his wife Helen, is second only to the Bill and Melinda Gates foundation in its spending on schools. Having spent over $1 billion to date on education reform, the Walton Family Foundation remains the largest donor toward initiatives supporting parental choice and encouraging competition in the education system…