After the conclusion of the 2021 MLB Draft, there are 241 (unofficial count) former participants who have had the opportunity to play professional baseball, most via the draft (there have been a couple of undrafted free agent signings).
The following 39 former participants have reached the Major Leagues... listed are their high schools, the year(s) they were in the event and current MLB organization (and/or current status):
BOLD = ON ACTIVE MLB ROSTER
RHP KYLE BARRACLOUGH (Wilcox HS, 2007) - TWINS
RHP ANTHONY BENDER (Casa Grande HS, 2013) - MARLINS
OF BRADEN BISHOP (St. Francis HS, 2010) - GIANTS (AAA Sacramento)
INF ALEX BLANDINO (St. Francis HS, 2009) - REDS (AAA Louisville)
RHP CONNOR BROGDON (Liberty HS-Madera), 2012) - PHILLIES
LHP KRIS BUBIC (Archbishop Mitty HS, 2013) - ROYALS
RHP TYLER CRAVY (Hogan HS, 2006) - FREE AGENT
3B J.D. DAVIS (Elk Grove HS, 2009) - METS
OF O'KOYEA DICKSON (George Washington HS, 2007) - FREE AGENT
LHP ROBBIE ERLIN (Scotts Valley HS, 2007/2008) – FREE AGENT
RHP CHRIS FLEXEN (Newark Memorial HS, 2010) - MARINERS
RHP DYLAN FLORO (Buhach Colony HS, 2008) - MARLINS
RHP DREW GAGNON (Liberty HS, 2007) - FREE AGENT
OF TYLER GOEDDEL (St. Francis HS, 2009) - FREE AGENT
RHP J.R. GRAHAM (Livermore HS, 2007) - RETIRED
OF MITCH HANIGER (Archbishop Mitty HS, 2007/2008) - MARINERS
LHP MARIO HOLLANDS (El Cerrito HS, 2005) – RETIRED
SS DREW JACKSON (Miramonte HS, 2010) - METS (AAA Syracuse)
OF BRETT JACKSON (Miramonte HS, 2004/2005) – RETIRED
RHP ERIK JOHNSON (Los Altos HS, 2006) – RETIRED
OF/INF TY KELLY (St. Mary's HS-Stockton, 2004/2005) - RETIRED
C ANDREW KNAPP (Granite Bay HS, 2009) - PHILLIES
IF/OF JEFF KOBERNUS (Bishop O’Dowd HS, 2005) – RETIRED
RHP EVAN MARSHALL (Homestead HS, 2006/2007) – WHITE SOX (60-day IL)
RHP CODY MARTIN (Dos Palos HS, 2006) - RETIRED
RHP JAMES MARVEL (Campolindo HS, 2010) - PIRATES (AAA Indianapolis)
INF/OF MARK MATHIAS (Irvington HS, 2010/2011) - BREWERS (60-day IL, had season ending shoulder surgery)
1B TOMMY MEDICA (Bellarmine Prep, 2005) – RETIRED
CF JOC PEDERSON (Palo Alto HS, 2008/2009) - BRAVES
OF STEPHEN PISCOTTY (Amador Valley HS, 2007/2008) - ATHLETICS (10-day IL)
2B TONY RENDA (SERRA HS, 2008) - FREE AGENT
RHP JOE ROSS (Bishop O'Dowd HS, 2009) - NATIONALS
SS MARCUS SEMIEN (St. Mary’s HS, 2007) – BLUE JAYS
RHP BRYAN SHAW (Livermore HS, 2004) – INDIANS
RHP BLAKE SMITH (DOWNEY HS, 2004/2005) - RETIRED
C MAX STASSI (Yuba City HS, 2007/2008) – ANGELS
RHP ROBERT STEPHENSON (Alhambra HS, 2009) - ROCKIES
C ANDREW SUSAC (Jesuit HS, 2008) - PIRATES (AAA Indianapolis, 60-day IL)
3B MITCHELL WALDING (St. Mary's HS-Stockton, 2009) - ANGELS (AAA Salt Lake City, 7-day IL)