When teaching proof for a topic sentence in a paragraph prior to teaching thesis statement for an essay, my best method to check understanding of proof was to use the film, A Christmas Story, which is a series of vignettes. After watching several of these vignettes, students had to pick one, choose a perspective as to whether it was the best, worst, funniest , and then write a short paragraph to prove how or why this scene was the best, worst etc. Then each group of 4 chose one to share with the class. If the paragraph just told the story, I explained so that the students knew it was not proof. After doing several of these, students could see that proof involved using the same ideas of what happened but phrasing them as proving the topic sentence. An example might be that the scene with Ralph helping his father with the tire and saying the bad word was the funniest scene. This scene was the funniest because Ralph says a bad word and his father and mother are horrified even though Ralph's father swears all the time. It is also funny because Ralph gets his mouth washed out with soap and the soap foams all over his face. When the idea of proof is clear, students wrote their paragraph again to prove their topic sentence and improve their phrasing, word choice or sentence structure. Because of the use of film, students almost never forgot the idea of proof which made teaching the essay so much easier.
When I taught 9th graders we often drew hamburgers on the board to organize and visualize our thoughts. The topic sentence (or bun) had to introduce and support their overall idea (or the burger and toppings would fall out). Aside from making them hungry right before lunch, they had fun assigning pieces of their sandwich to the diagram and then checking to make sure it all fit together. After doing a few burgers on the board, they did their own. When I had them again as seniors they still remembered their hamburger paragraphs.
I like to teach students that writing is a process, one that requires revision and rewording. You can teach them an outline format first, with brainstormed specifics about the question or prompt, then cobble together one specific sentence that answers the question using what's in the outline, along with one sentence for each of the main points explaining them. They can then use the outline to rewrite an organized paragraph with a crude thesis.
I agree with you, post 6. My post got too long to include everything, but yes, the why is that funny was supposed to be there. Post 8, I have often cut up paragraphs to put back together as strips of paper so that the group can move them around and together figure it out before they each get their own to do. Scissors and tape worked well to keep them on task as I could see the results easily. Paragraphs from Twain worked really well for my upper level students. I love all the ideas here!
I have actually cut up example paragraphs and asked students to reassemble them so they have hands on experience of identifying the topic sentence and putting it into its position. This really helps them when they come to write their own paragraphs.
I always tell me students to ask themselves "why" when they write a sentence and then write the "answer" to the why. This forces them to explain why their proof is proof. Using your example above: It is funny when Ralph has soap all over his face (WHY?) because he looks silly and foolish. It is never too early to get them to at least start to see the importance of higher order reasoning. Just because they think something is proof doesn't necessarily make it so.
These are all good suggestions. In essence persuasive writing is a written debate. In light of this, I like to have debates in class. When you get the students to debate each other on various topics, then they start giving reason and reason. This exercise can be, then, translated into teaching students about the importance of thesis statements and topic sentences.
Great ideas in previous postings! The key, at any age but particularly with middle schoolers who aren't much interested in topic sentences or paragraphs, is to catch their interest through very personalized activities. Ask them to write a description of their idea of a perfect meal and explain why each item is included - the summary of the meal is the topic sentence, as students will hopefully recognize when they review each other's paragraphs. Have them write about a recent school event - athletic contest, school dance, whatever - and then analyze their paragraphs to identify the topic sentence within what they wrote.
While I use samples of paragraphs for my students to read, I love both of the ideas presented by the postings above. I have to agree that topics which interest students are the ones that they are more willing to work longer with. Outside of practice, practice, practice, I think that finding "fun" ways (like with the movie) are the best ways to insure mastery.