Here's a compilation of World Junior results (at least the ones I have). Skaters who have gone on to medal at Senior Worlds are in bold type. Many skaters who didn't win medals at Worlds may have medaled at the GP and/or Euros/4CC.
JUNIOR WORLDS
1994
MEN: Weiss [age 17], Shigematsu, Michael; (4) Yagudin [age 13], (11) Kulik [age 16]
LADIES: Kwan [age 13], Czako, Slutskaya [age 14]
1995
MEN: Kulik, Cerez, Suzuki; (14) Goebel [age 14]
LADIES: Slutskaya, Ivanova, Czako; (4) Lipinski [age 12]
1996
MEN: Yagudin, Honda, Guo; (6) Plushenko [age 13], (7) Goebel
LADIES: Ivanova, Pingatcheva, Kanaeva; (4) Suguri [age 15], (5) Lipinski Note: Lipinski was 15th at ’96 Senior Worlds.
PAIRS: Maksuta/Zhovnirsky, Fionenko/Marchenko, Hartsell/Hartsell
DANCE: Davydova/Kostomarov, Delobel/Schoenfelder, Gudina/Kurkudym; (9) Belova/Staviyski
1997
MEN: Plushenko, Goebel, Guo
LADIES: Vogel, Sokolova, Ivanova; (4) Suguri
DANCE: Ulanova/Stifounin, Potdykova/Petukhov, Blasowska/Lozubek
1998
MEN: Delmore, Davydov, Yunfei Li; (4) Klimkin [age 18]
LADIES: Soldatova, Ivanova, Volchkova
PAIRS: Obertas/Palamarchuk, Nikolaeva/Sokolov, Maksuta/Zhovnirsky
DANCE: Joseph/Butler, Faiella/Milo, Potdykova/Petukhov
1999
MEN: Klimkin, Restencourt, Takeuchi
LADIES: Timoshenko, Hughes [age 13], Volchkova
PAIRS: Obertas/Palamarchuk, Handy/Binnebose, Maksuta/Zhovnirsky, (8) Pang/Tong
DANCE: Silverstein/Pekarek, Faiella/Milo, Romaniuta/Barantsev
2000
MEN: Lindemann, Restencourt, Savoie; (4) Klimkin, (10) Lambiel [age 14] Note: Restencourt was 9th at 2000 Senior Worlds
LADIES: Kirk, Stellato, Meier; (6) Cohen (7) Nakano
PAIRS: Savchenko/Morozov, Obertas/Palamarchuk, Shapiro/Sokolov; (4) Zhang/Zhang
DANCE: Romaniuta/Barantsev, Nussear/Forsyth, Belbin/Agosto
2001
MEN: Weir, Lysacek, Restencourt; (5) Lambiel, (7) Buttle, (11) Shubin, (12) Dobrin, (16) Van Der Perren
LADIES: Oblasova, McDonough, Poykio; (4) Nakano, (8) Rochette, (11) Kostner
PAIRS: Zhang/Zhang, Kawaguchi/Markuntsov, Roth/McPherson
DANCE: Romaniuta/Barantsev, Belbin/Agosto, Khaliavina/Shabalin
2002
MEN: Takahashi, Van Der Perren, Timochenko; (14) Griazev
LADIES: McDonough, Nakano, Ando; (4) Liang, (5) Rochette, (9) Ota, (10) Kostner
PAIRS: Riabchuk/Zakharov, Karbovskaya/Slavnov, Ding/Ren
DANCE: Belbin/Agosto, Khaliavina/Shabalin, Romanovskaya/Grachev
2003
MEN: Shubin, Lysacek, Preaubert; (5) Dobrin
LADIES: Ota, Ando, Kostner; (6) Liang
PAIRS: Zhang/Zhang, Ding/Ren, Don/Hunt
DANCE: Domnina/Shabalin, Hoffmann/Elek, Romanovskaya/Grachev (11) Matthews/Zavozin
2004
MEN: Griazev, Lysacek, Brauninger; (8) Dobrin, (11) Oda (20) Othman
LADIES: Ando, Meissner, Taylor; (12) Gedevanishvili, (16) Korpi
PAIRS: Shestakova/Lebedev, Dube/Davison, Mukhortova/Trankov
DANCE: Romanovskaya/Grachev, Hoffmann/Elek, Matthews/Zavozin; (4) Mikhailova/Sergeev, (11) Virtue/Moir, (13) Davis/White
2005
MEN: Oda, Pensero, Dobrin;
LADIES: Mao Asada, Kim, E. Hughes; (4) Meissner, (5) Gedevanishvili
PAIRS: Mukhortova/Trankov, Dube/Davison, Kokoreva/Golovkin, (9) Vlassov/Meekins
DANCE: Matthews/Zavozin, Virtue/Moir, Gorshkova/Tkachenko; (5) Mikhailova/Sergeev
2006
MEN: Kozuka, Voronov, Ponsero
LADIES: Kim, Mao Asada, Zukowski,
PAIRS: Vlassov/Meekins, Moyle/Seitz, Krasilnokova/Bezmaternikh
DANCE: Virtue/Moir, Mikhailova/Sergeev, Davis/White
Some notes based on previous remarks:
Tara Lipinski was probably having a bad year when she finished 5th at JW in 1996, because she went on to Senior Worlds and finished 15th.
Vincent Restencourt had competed at Junior Worlds twice before receiving the first of 3 JW medals. In 2000, he finished 9th at Senior Worlds after medaling at JW; 2001 was his last year of eligibility, and he would have been 18 or 19 to Weir's 16 and Lysacek's and Lambiel's 15. Lambiel had a good QR and SP, but was 7th in the FS, finishing 5th overall. But 5th was a big improvement over Lambiel's 10th place in 2000. Lambiel did not compete in 2002 and may have been experiencing problems with his knee at that time.
It seems to me from looking at the JW results that many medalists (and non-medalists as well) have gone on to success at the senior level. Some medalists proved to be early bloomers who either faded as their bodies matured, or who could not remain competitive with their seniors.
One interesting observations: the many partner changes in both Pairs and Ice Dance. Many halves of the Pairs medalists went on to success with other partners at the Senior level. And it is truly amazing how many Russian Junior Pairs and Ice Dance teams disappeared off the radar after medaling as juniors. Their splits and re-pairings are just as or more numerous than those of US teams who have had nowhere near as much success.