Our Founders

tom crone

Tom Crone
7th Degree Judo Black Belt

Tom Crone began his judo training n 1960 as a freshman at Mankato State College, Mankato, Minnesota. He rose to the rank of shodan (1st degree black belt) in three years, having won successive state championships and placing in the First Collegiate National Championships in Colorado Springs, CO, in 1962.

In 1985, he and Michelle Holtze founded North Star Martial Arts Academy. Since, he has trained at the Kodokan Judo Institute, served five years on the National Junior Olympic Coaching Staff, served Judo Minnesota as its Development Chair for 10 years, one term as President, and in 2002 became its Collegiate Committee Chair. He is a member of its Standards Committee. In 2003 he also became the Midwest Coordinator for the United States Judo Association's Collegiate Committee, and its Chair in 2004.

Crone sensei became the first home-grown Minnesota judoka to reach the ranks of 6th and 7th degree black belt awarded by a nationally accredited judo organization. He has been the instructor for the University of Minnesota's academic credit course since 1995. He is Sensei Emeritus of North Star Judo.

Michelle Holtze (deceased)
8th Degree Judo Black Belt

Aug 17th 1954 to Aug 3rd 2016

Michelle Holtze started judo as a teenager in 1969. She began teaching judo while a student at Mankato State. Upon returning to the Minneapolis area, she eventually took over teaching at her instructor’s school, West Bank Judokan. This evolved into her becoming the co-founder of North Star Martial Arts Academy.

Michelle served as the Standards Committee Chair (Promotion Committee) for Judo Minnesota for several years, and held a variety of other JMI positions.

She and her Kata partner were the first competitors to step foot onto the mat for the Pan American Judo Competitions, and won a silver in ju no kata that day in 2000. In the new millennium, Michelle has won numerous national and international kata medals, including the one shown in the photo which is a 1st place for nage no kata at the 2003 World Masters Judo Championships, at the Kodokan in Tokyo.

Michelle was the first Home-grown Minnesota woman to be awarded the rank of 6th and 7th dan. She also held coaching certifications with all three accredited national judo organizations. In 2005, she was elected to the Board of Directors of the United States Judo Association.


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