Pell Grants were $22.8 billion, Title I Grants to Local Education Agencies (called College and Career-Ready Students now), was $14.5 billion. Special education grants to states was $11.6 billion (IDEA is state level, not municipal level, my mistake). $48.9 / $68 = 72%.
There are some more in there too ($0.1 billion in grants for Indian education, etc), but those three are the budget drivers.