2009-10: A native of Erie, Colorado, Jaccob Slavin skated for the Colorado Thunderbirds. He played 13 games with the club's U16 team and had one assist on a team that won 18 of 19 games in league play. Slavin did not participate in the Tier 1 National Championship tournament where the Thunderbirds were a perfect 9-0. In 30 games with the Thunderbirds' U15 team he scored 5 goals with 11 assists and had 2 penalty minutes.
2010-11: Slavin appeared in 17 USHL games with the Chicago Steel, skated in 15 games for the Colorado Thunderbirds' U18 team and was a captain for the Thunderbirds' U16 squad. He scored 1 goal and was minus-15 with 10 penalty minutes during his time with the Steel. Chicago finished with the USHL's worst record – winning just nine games. In 15 U18 games Slavin scored 1 goal. In 24 games with the U16 squad in the first half of the season he scored 3 goals with 16 assists and was plus-26 with 14 penalty minutes. Slavin committed to playing college hockey at Colorado College in 2013-14.
2011-12: Slavin was the leading scorer amongst defensemen for a much-improved Steel team in his first full USHL season. Slavin was third amongst all Steel skaters with 27 assists and scored 3 goals with 12 penalty minutes and a plus-six plus/minus in 60 games for Chicago. The Steel finished three points out of the final playoff spot in the Eastern Conference; winning 25 games. Not among the 210 North American skaters in Central Scouting's final rankings prior to the 2012 NHL Draft, Slavin was selected by Carolina in the fourth round (120th overall).
Slavin will begin his college career in the fall of 2013 when he attends Colorado College.