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She made up her mind to go to college.
Literal
She [topic-は] college [to-へ] let-me-go [intent-と] resolved.
決心する ('to resolve, to make up one's mind') takes its content via the volitional + と construction: 行こうと決心する ('resolve to go,' literally 'thinking I'll go, resolve [it]'). The volitional 行こう carries the content of the resolution; と marks it as the quoted intent. Compare 行くと決心する (less common, with the dictionary form, which feels somewhat detached) — the volitional version captures the speaker's first-person commitment more vividly.