This unit gives students the chance to learn more about their inherited physical characteristics. Mr. WcWeeny tries to engage his students throughout this unit (as in all his units) with a personal challenge that is relevant to them and requires them to apply their new knowledge of a subject. Mr. McWeeny introduces Mendelian Genetics by having students study a chapter as done traditionally in schools (a skill he believes is very valuable). Students learn that Mendel crossed pure plants showing contrasting traits to produce new (hybrid) plants. Students then study plants and their traits by dissecting a flower. "We diagramed it and listed all the parts and then we actually took the flower's different parts and labeled it Petals, leaf ..."   One student joked, "I had fun going home and saying today it was so gross I dissected a flower (because you know, it is not gross)." The students then learned how a flower makes a seed by listing all the steps on their own and then by then listing the steps with Mr. McWeeny. They then learn how to do Punnet Squares.       Mr.McWeeny then has students apply Mendel's Rules to their own family's traits by having them make a family tree . The family tree assignment Mr. McWeeny hands out looks like this: If you cannot read this assignment, the main three points of the handout read: I. If you do not have phenotypes for your grandparents and one cousin's family, HAVE MR.MCWEENY MAKE SOME UP FOR YOU!! NOW!! RIGHT AWAY!! TODAY! II. If you do not have PROOF of dominance for any trait, first research other families and then just state what you are using as dominant and why you could not prove dominance. III. Make a FINAL COPY of your tree NEAT, and large enough for all information and assignments.   Once the family tree is completed, students pick three or more traits to research. Contrasting traits, complete or incomplete dominance, multiple traits, multiple allesles, or even "suspected" traits are some research options. This way the student with musical ability can trace his or her suspected trait through his or her family and determine if the trait follows Mendel's rules. This next step requires collecting data. Beside each figure on their tree they list the phenotypes for each trait. Then they determine dominance by applying Mendel's rules. Once dominance is determined, symbols are identified and the genotypes for each individual are entered into the figure on the family tree. From these, Punnet squares can be constructed for a variety of situations. One student did a simple Punnett Square comparing height:   "I like to have the students do a cross for their parents and determine their chances of being what they are. They can also do a cross between themself and a fictitious mate, or do a backward cross to determine unknown traits. In the end all of this research and information must be presented neatly in a contained package for grading. I use a Rubric that has five levels of performance (poor to excellent) and five criteria. (Presentation, research, predictions, knowing and thinking). s One student's graded rubric looks like this: "In this project the students are challenged to collect original data and then apply scientific concepts to determine answers to a variety of meaningful questions... "I think the most satisfying feedback from this project is when students figure out the chances of themselves being what they are for just three traits (usually less than 1/16) and then extrapolate to the thousands of traits they have and the fact that they are what they are is 'one in a trillion' ... Each person is very special."   The students liked the unit ... "We did Punnett Squares ­ single crosses, and went through some examples ... I liked it. I thought it was kind of neat." I don't know why I liked doing Punnett Squares but I thought they were fun ." "It was fun because you got to make cute little squares ...And we learned that the dominate trait is always capital and the not dominate trait is lower case." After this unit, "You know a lot more about why your hair is the color it is ... And which side of the family you got which trait from ... you could do anything like strait fingers ... eyebrows or freckles ... I got my right-handedness from both sides of the family."   I liked how you could predict what your baby sister or brother would look like And or if you had children and your husband like either had dominant traits or recessive traits so you could predict your child Some of the things the students liked most about the unit were: We can now predict what people would be like Or if we wanted to expand into our future about genetics we could we would have an idea You could figure out genes in the past like your great, great, great, grandfather Some cancers and stuff are hereditary and if you can figure out if you might have it and what your chances are, you have a better chance of surviving You have to learn about this for high school It helps (to learn about genetics) You don't randomly end up the way you are You are like that because your parents are like that You learn about recessive traits and that your parents might not have any of the traits you have and then that can only lead to your grandparents having those traits It was important to learn about the past or the future and where your genes come from I learned that my whole family except my mother at one time had braces That might come in handy We will want to know if the kids will need braces Put aside some money I did the future So funny You could make yourself an imaginary husband and see what your kids would look like I named them and everything I did left-handedness and I heard that a lot of left handed people die in accidents My sister always tells me that she thinks she is going to die (she is left handed) I liked it wasn't just like memorization There was math to do There were books but not too many   To end the unit, students were given a test ... In which they had to determine traits of some rather odd things ... "The test it was fine, OK ... It wasn't boring ... Most tests are boring ... On the test we had monsters and stuff so that was fun ... You also got to draw stuff instead of writing it so I drew stuff because I can't write as well ..." One student summarized the Family Tree experience this way: I liked the family tree. It was hard but you got to ask a lot of questions and we learned a lot ... It was hard because we had never done anything like it before.

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A Year of 8th Grade Science Contents Introduction Bill's Teaching Biography Bill's Most Influential Books Bill's Teaching Philosophy An Interview with Bill McWeeny The Classroom Environment Setting Up the Year: Throughlines Setting Up the Year: Notebooks The Culturing Unit The Genetics/Family Tree Unit     - Implementing the Genetics/Family Tree Unit     - The Genetics/Family Tree Unit and TFU     - The Genetics/Family Tree Assignments and Student Work The Cell Unit The Body Systems Unit Pictures of Practice Contents Introduction The Colonial Biography Unit (7th Grade History) A Year of Seventh Grade English A Year of Eighth Grade Science The Jazz Unit Snapshot Using the CCDT to Develop Generative Topics Teaching for Understanding Quick Menu - select a destination - INFORMATION   What's Understanding?     - An Interactive Look at Understanding   What's Teaching for Understanding?     - A Performance Criterion   What's the TfU Framework     - Throughlines     - Generative Topics     - Understanding Goals     - Performances of Understanding     - Ongoing Assessment PICTURES OF PRACTICE   The Colonial Biography Unit (7th Grade History)   A Year of Seventh Grade English   A Year of Eighth Grade Science   The Jazz Unit Snapshot   Using the CCDT to Develop Generative Topics COMMUNICATION CURRICULUM DESIGN TOOLS   Planners   Tip Sheets   On-line Tools

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