。
She got good grades in English.
Literal
She [topic-は] English [in-で] good grades [object-を] took.
成績 ('grades / academic performance') sits at a different scale from 点 ('a single test score'). The distinction matters: 点 is a numeric score on one exam, while 成績 is the broader academic record — closer to 'grades' or 'performance,' summarizing a student's standing across assessments. 成績がいい ('good performance') is the typical adjectival pairing; 成績を取る is the active counterpart, framing the record as something acquired through effort. The で marks 英語 as the domain — 'in English (as a subject area).'