While reading the question asked by DVK, I wondered when Anakin became eligible to train his own Padawan. At the conclusion of Star Wars: Episode II - Attack of the Clones Anakin is still considered Padawan learner and during Episode III - Revenge of the Sith Anakin complains to Palpatine that he is ready for the Master trials but Master Yoda doesn't think so. Yet in the cartoon series The Clone Wars he has his own Padawan, Ashoka.
It was in the 2003 series (directed by Genndy Tartakovsky), not the CGI ones. In the first episode of season 3. You can see the episode list in Wikipedia.
In the "Legends" canon, Anakin was knighted in a secret ceremony after the Battle of Praesitlyn without the customary trials because he has proven to be a worthy Jedi during the Clone Wars.
In the new Disney canon his 'graduation' has not been addressed.
More info about this in Wookieepedia.
Anakin is knighted and loses his braid at the end of Clone Wars: Chapter 21
Yoda knights Skywalker, cutting off his Padawan braid, which C-3PO later presents to Amidala, which she happily stores away with her Japor snippet for safekeeping. In return, Amidala gives R2-D2 to Skywalker, the droid showing the new Knight a hologram recording of Amidala presenting him the gift and accepting his own.