What does it take for a teacher to be struck off?

Stuff reports on how a teacher called Ngamihi Moses did the following:

• On a school camp instructed six misbehaving year eight students to get into a van
• Dropped them off 10 km from camp to an area unknown to them
• Told them to walk either 200 km back home to Whakatane or 10 km back to camp
• Drove off
• Kids split into two groups of three
• 20 minutes later the teacher picked up the kids walking back to camp
• Could not find the kids walking to Whakatane
• After midnight the other three kids were found
• The teacher then punished the kids who tried walking to Whakatane by stripping them to their underwear and made to stand outside in the cold until they apologised

For all that he merely gets to go on a course, and have mentoring for a year and have to tell future employers for just two years. Then it is all wiped.