At Westfield High School in Houston, Peavy was a three sport star. In addition to football he was the starting point guard in basketball and a District 13-5A champion in long jump in 2013. His junior season he tallied 49 tackles and two interceptions on his way to a 12-1 record. His senior season he posted nine interceptions, 38 tackles and three touchdowns finishing with a 13-1 record. He was named First-team All-district 13-5A in both his junior and senior seasons.
After redshirting his initial college season Peavy made his debut in 2015. He led the team in tackles, passes defended, and interceptions with 82, 10, and two respectively. His 82 tackles were second most among Big 12 freshman. In his Cyclone debut against UNI Peavy had seven tackles, including a tackle for loss, and he defended two passes. Against Toledo he had his first career interception on top of six tackles and three pass breakups. He had 10, nine, and 12 tackles against Kansas, TCU, and Oklahoma State respectively. He was named to the Honorable Mention All-Big 12 team as well as the ESPN.com Big 12 All-Underclassman team.
2016 season
In 2016 Peavy built upon the success of his freshman campaign. He once again led the team in passes defended with 11 and was fourth on the team in tackles with 62. His 12 pass breakups were good enough for fourth in the Big 12. Peavy had another strong outing against UNI with five tackles and a forced fumble. Had got his third career interception and defended two passes against San Jose State. His season-high in tackles was eight against Oklahoma. Following the season he was once again named to the Honorable Mention All-Big 12 team as well as the ESPN.com Big 12 All-Underclassman team.
2017 season
Peavy continued his success on the field in 2017. He was first on the team in pass breakups with seven and third in tackles as well as second in interceptions with 81 and two respectively. Against UNI he 10 tackles, one for a loss, an interception and a pass breakup. He had seven tackles and a 70 interception against TCU. In his strongest outing of the season against Baylor Peavy made nine solo tackles, two for a loss, broke up a pass, and both forced and recovered a fumble. He earned Big 12 Defensive Player of the Week honors for the feat. He was named Second-team All-Big 12 by both the coaches and AP.
