Calson died in the absurd way children died, climbing for mangoes in a tree hung with powerlines or in the stream overflowing with sunflowers where they drowned. Calson died under an unsterile surgical knife, not a scalpel, I imagine, but a cutlass, the same eager instrument my students used to clear the field outside our classroom. This was to discourage green mambas, but every so often I imagined a scream rising from the grass, not from the child bitten but from those who would live to see him die. You are aware of my assignment, Mom. I teach middle school math in a lonely corner of Cameroon. All day the sun’s orange fist pounds the zinc roof, while I pound arithmetic into my students’ heads. The sun’s orange breath seeps between the long rows of desks, lifting plumes of dust that cling to my damp forehead and snowflake into my eyes. Mom, these are the conditions we must suffer, all in the name of common denominators, which continue to elude my students. Only Calson could add fractions, the reason I noticed him at all. “Why is Calson the only person who understands common denominators?” I asked one oppressive afternoon as I wrote ¾ + ½ on the board. “Calson, come show the class how to solve this.” Two big eyes floated up to the chalkboard on a spiral of dust, collarbones swimming on his narrow shoulders. He was smaller than the others. He couldn’t reach the equation so he rewrote it lower on the cracked slab of concrete. “Multiplying two over two is the same as multiplying by one.” “The same as multiplying by one!” the class muttered. A hundred hands scribbled in their notebooks after him. “That’s what I’ve been saying this whole time!" I said. "Apparently I should have Mr. Calson teach fractions from now on.” A smile spread over his sweating face, stuck there like petals after the rain. “Now sit down so we can move on to something new.” He was still smiling a few days later when I snapped at him for sleeping in class. “I’m not sleeping, Madame.” I tottered over, my heels catching on the knuckled dirt floor. Across his notebook sidled careful rows of equations. “Why are you lying down?” “It’s his leg,” the other students chorused. “His leg is paining him.” “His leg?” I asked, rounding his bench. He had it elevated inside the desk. It looked swollen. “Okay, just don’t fall asleep.” “No Madame, I won’t.” He died a few weeks later, although it was over a year before I found out. I was sitting beside Mispaline in her crowded kitchen as she prepared fufu. I didn’t know Mispaline well, but that day she had invited me over for lunch. “You know Calson?” she asked unexpectedly. “Your student Calson?” “Yes.” Actually, I'd forgotten about him. Someone else had filled his space in my mind, just as someone else had figured out how to add fractions. Mispaline’s words conjured him back. “He gave up the ghost.” She stood up. “Your student Calson died.” “Oh.” The smoke from the fire stung my eyes. The smoke turned my head in nauseating circles. “Do you want to see pictures?” Someone pulled out a smartphone and leaned close. “I have pictures of his leg when they cut if off. It was green and oozing and covered in…” “Calson,” Mispaline cut in, as though his small form could fit into a name. “He was my little brother.” “Oh. I didn’t know.” In the end that is not the end I lived and my student died. In the end I will go home to the U.S., where despite my crappy student insurance someone will always pay for me to have the best healthcare humans can provide. When I jumped off the cliff of depression last month I had forgotten, once again, my student Calson. I had forgotten how much he probably wanted to be alive. How something as mind dulling as adding fractions had brought him joy. This is why I wrote you this letter, Mom--which is not in fact a letter but a lingering taste of blood in my mouth that I have not been able to rinse clean.