The Marine Corps Scholarship Foundation (www.marine-scholars.org) has served that purpose quite admirably since 1962. The children of a number of my fallen friends had their tuition paid by the fund, so I can attest to its mission and its success. It is a well-managed charity.
A newer foundation is the Marine Corps-Law Enforcement Foundation (www.mc-lef.org), which was expanded to include law enforcement after 9/11. It has an outstanding board of directors, some of whom I know personally or have served with, and all of whom I greatly respect. The foundation has no employees; virtually all expenses are absorbed by its officers and volunteers, so all gifts will reach their intended recipients.