My 10th grade Biology teacher, Mr. Ofsiani (more commonly called Mr. O), was one of those neat teachers that stick out in your memory. His entire classroom was covered in interesting things, from comics clipped from newspapers and hung on the walls to a skeleton hanging from the ceiling to the live iguana in the back of the room. He loved his subject and got excited about doing hands-on experiments instead of just going through the textbook and running tests. He was short, bearded, and completely bald, but he was also vibrantly engaged with life.
The first quarter of his class was devoted to plant identification. Looking back, I'm not sure how he got this past the school board, but we essentially spent the first two and a half months of school filing into the classroom, taking roll, and then filing out again and going for walks in the woods next to the school. We did, technically, learn plant identification and I believe there was even a test at the end that gave you leaf shapes or bark pictures and had you give the name of the plant, but I learned more than just plants.