As someone who went to middle school, and did so in the 1980s when Cesar Chavez was still alive, I'll say yes. We were taught about him, about his struggles with the grape farmers and about United Farm Workers. From a scholastic standpoint, it's just a very matter of fact story about labor unions.
Probably among the more recent and one which students could relate to in history, Cesar Chavez would make a great subject for middle school students. The fact that the culture he fought for is still so prevalent today, and the problems he stood against still exist today, there is a great reason that Cesar Chavez should be taught to middle school students.
Any subject can be taught effectively in middle school if given the right treatment. Cesar Chavez is an historical figure just like any other. As a migrant farm worker, his story is just as valid as those of John Steinbeck and Woody Guthrie. As a civil rights activist, Chavez can be taught alongside Dr. Martin Luther King Jr and Mahatama Gandhi. There are plenty of places to insert Chavez into classroom curricula.
I believe middle school students could be effectively taught about Cesar Chavez at the middle school level. He is best known for his work on the National Farm Workers Association and promoting workers rights. The only problem with introducing this figure to middle school age children is rather or not they would really connect with the topic and find interest in it.
I do not believe that Cesar Chavez can be taught effectively at the middle school level. I do not think middle school age children are mature enough to fully understand the plight of farm workers during his lifetime. I feel high school freshmen or sophomores would be more able to relate to the hazards and struggles that had to be endured daily. Older children would understand the fight for civil rights more than those in middle school.