They seem fine to me. I read a number of them in 7-8th grade and
   that was back in ... 1984/1985. Some I read in 6th grade like
   Huck Finn and Tom Sawyer. A few I read in 9th. I'd say it's on
   target.

   I've either read them all, or have a basic familiarity with
   them. Call of the Wild was 7th grade and that book haunted me
   for quite some time.

   I also read "Clan of the Cave Bear" in 7th Grade. I didn't know
   it was a prehistoric romance novel. To me, it was about this
   first human lady and I was fascinated by the different culture
   of the Neadrathals from what I was accustomed to. Thoroughly
   enjoyed it.

   I read the sexy scenes too but since it happened 125000 years
   ago, I figured that was normal for the time and I knew it was
   fiction in any case.

   One teacher was a little scandalized that I read it. She was not
   happy at all. I read it because it looked interesting in the
   public library and you know what? It was.