Andrew was a freshman at Oregon State in 2012-13. 

He was named the Pac-12 Freshman of the Year, a Pac-12 all-star, a second-team Louisville Slugger All-American, a Louisville Slugger Freshman All-American and a semifinalist for the College Baseball Hall of Fame's Pitcher of the Year award.

He was the Pac-12 Pitcher of the Week and the  National Collegiate Baseball Writers Association National Player of the Week for May 13-19 for a two-hit shutout of Oregon, and was a College Sports Madness second-team Pac-12 all-star.

One of the most decorated pitchers in state history during his career at North Eugene High School, Andrew was Oregon's 5A Player of the Year in 2012, the co-5A Pitcher of the Year in 2011 and 2010, and a three-time all-state and four-time all-league selection.

He was also the South's Most Valuable Pitcher in the Knights-run Oregon All-Star Series in June. 2012. He was 9-1 as a high school senior, with a 0.76 ERA and 125 strikeouts in 72.2 innings. He also hit .400, with a homer and 21 RBIs as a shortstop when not pitching.

In four years at North Eugene, Andrew was 32-10 overall, with 441 strikeouts in 300 innings.