Some 63,000 Minnesota high school juniors will take perhaps the biggest standardized test of their lives Tuesday.

Minnesota this year is joining 20 other states that sponsor the ACT for all students. Juniors now must take the test — or one of a handful of similar exams — in order to graduate, but no minimum score is required and the results are not used by the state to identify good and bad high schools.

This is the third year Austin Public Schools will have all its juniors take the ACT tests.

About 76 percent of last year’s graduating seniors across the state took the ACT on their own on a Saturday at a cost of about $54 — or free for those who qualified. That figure should approach 100 percent next year with the state picking up the $4.2 million tab, starting with this year’s juniors.

The change has pushed St. Paul and other school districts to take on a greater role in preparing students. St. Paul is paying the Princeton Review between $42,000 and $98,000 to provide test-prep sessions for the ACT, the entrance exam widely used by Midwest colleges.

Anoka-Hennepin schools have beefed up their online test-prep tool and embedded elements of the ACT into high school English and science classes.

Minneapolis Public Schools for years has offered free ACT test-prep and is doing so again this year.