Do I have to wear a helmet while operating a motorcycle? Moped?

Anyone who drives a motorcycle must have a Class M motorcycle license or motorcycle instruction permit.
Moped drivers do not have the same licensing requirements. They must have a Class D regular, probationary, or special license restricted to moped use.
A person must hold a Wisconsin motorcycle instruction permit or surrender a valid motorcycle license from another state before they may obtain a Class M license.
Instruction permit
To obtain a motorcycle instruction permit, the applicant must pass the motorcycle knowledge test, a sign test and a vision screening.
If under age 18, the following are also required:
·        Be at least 16 years old
·        Have a sponsor
·        Provide proof of Driver Ed completion
·        Provide proof of enrollment or completion of a Basic Motorcycle Rider Course
Some restrictions apply during the period the instruction permit is held:
·        Must wear eye protection
·        Must wear an approved helmet
·        Permit holders may ride alone during the day.
·        If cycling after dark, the permit holder must be accompanied by a person at least 25 years old with two years licensed driving experience and a Class M motorcycle license.
Skills test
The applicant must demonstrate competency in motorcycle operation by passing a Wisconsin Department of Transportation (WisDOT) administered motorcycle driving skills test or providing a waiver showing completion of WisDOT approved Basic Motorcycle Rider Course.
For the WisDOT driving skills test, the applicant must provide a cycle in good working order and wear eye protection and an approved helmet.
Skills tests are conducted by appointment at DMV service centers located throughout the state.
Motorcycle violations
Successful completion of either the Basic Rider Course, or the Advanced Rider Course can also be used to reduce your driving record demerit points for motorcycle violations by up to 3 points, which you have been convicted of during the prior 12 months. A person is limited to only one point reduction every five years.
Courses are provided throughout Wisconsin and through the riding season by training sponsors in various locations.
Motorcycle Skills Test Waiver Program
Upon successful completion of a Basic Motorcycle Rider Course, the motorcycle riding instructor issues each student a signed waiver authorization form. This form is usable only one time and only by the person to whom it is issued. When other licensing requirements have been met and the waiver form is presented at the DMV service center, a Class M endorsement will be added to the person's driver license.