The Forest of Chakra

is episode 10 of the original Naruto anime.

Synopsis
Kakashi rests and recovers at Tazuna's home. There, he makes the observation that Zabuza's death was odd, and concludes that it was an act. Elsewhere, Haku revives Zabuza, who promises to crush Kakashi when next they meet. Both Kakashi and Zabuza need to rest a week to recover. With Zabuza's return a likely outcome, Kakashi takes Team 7 to the nearby woods for chakra training, where they learn to walk up vertical surfaces. Sakura performs this perfectly the first time, but Naruto and Sasuke require extra training. Naruto asks Sakura for advice, and Sakura agrees to help him. Kakashi makes the observation that Naruto is finally getting a good grasp on teamwork.