Orochimaru trained Kabuto [Strongest Shinobi in History after Obito and Rikudō Sennin], Sasuke [Top 6-10 Material], Kimimaro [Extremely Powerful], Sound 4 [Strong for Age/Time] as well as Team Dosu [Strong for Age]. In addition, he probably indirectly trained everyone in Otagakure who were doing relatively good in the beginning of the Invasion of Konoha but were obviously after a while overwhelmed.
Orochimaru, when training Sasuke gave him the Sword of Kusangi, taught him many Chidori Variants, Genjutsu, awakened the 3T and when he came back was able to move extremely fast. Naruto and Yamato were unable to react and had Sasuke wanted to, I would argue that he would have killed Sai, Naruto, Sakura and Yamato right there.
Jiraiya and Minato's relationship is unknown and we don't know how Minato learned FTG. Naruto didn't seem to actually learn too much from Jiraiya other than Genjutsu Repelling and Rasengan variants it seems. Nagato seems to have learned most of what he did subsequent to Jiraiya leaving. Konan and Yahiko don't have enough feats.
Minato trained Rin, Obito and Kakashi. Kakashi was already a prodigy and needed very little training. It seems that Obito didn't know too much [for his age or an average ninja] before Madara took him under his wing. Rin died before we saw enough from her so we can't judge based on her.
Kakashi seems to be an awesome teacher and he is but I think that the Sannin taught Team 7 more than Kakashi. What did Sakura really learn from Kakashi other than Genjutsu repulsion? Sasuke learned Chidori and a few minor things but most of what he learned was from Orochimaru. Naruto learned RFS from Kakashi [not taught, by trained] but this was based much off Jiraiya's training.
Tsunade seems to be a good teacher but only taught her own techniques to her pupils. For variety, she isn't too good a teacher imo. Danzou has shown very little teaching skills and Gai, as good a teacher he is, is based off Taijutsu alone. Asuma is a good teacher but not a great teacher imo.
I would defect to the ♪.