Spaghetti Bridge Unit – Cross Curricular (Math, Science, Language Arts) Shane Dempster Julie Watkins Preparation In science class, the four main types of bridges (truss, beam, suspension, and arch) will be introduced, discussed, and diagramed. The students will be shown pictures of other spaghetti bridges from other contests. Students will be divided into groups of 3 (list top 3 and bottom 3 people for partners, teams made by Mr. Dempster & Miss Watkins). Scenario The town of Pastaville is expanding every day. A peaceful river crosses the town. Houses are built along both shores of the river, but there is no bridge to link them. The only material available to build a bridge is . . . spaghetti! Can you build a spaghetti bridge? Your challenge You must build a 60-cm long bridge using only spaghetti, spaghettini or linguini. At its centre, the bridge must be able to support a two-kg load. Objectives Outcomes for Science, Technology and Society (STS) and Knowledge Students will: • interpret examples of variation in the design of structures that share a common function, and evaluate the effectiveness of the designs (e.g., compare and evaluate different forms of roofed structures, or different designs for communication towers) • identify points of failure and modes of failure in natural and built structures (e.g., potential failure of a tree under snow load, potential failure of an overloaded bridge) • recognize and use units of force and mass, and identify and measure forces and loads • identify examples of frictional forces and their use in structures (e.g., friction of a nail driven into wood, friction of pilings or footings in soil, friction of stone laid on stone) • identify tension, compression, shearing and bending forces within a structure; and describe how these forces can cause the structure to fail (e.g., identify tensile forces that cause lengthening and possible snapping of a member; identify bending forces that could lead to breakage) • analyze a design, and identify properties of materials that are important to individual parts of the structure (e.g., recognize that cables can be used as a component of structures where only tensile forces are involved; recognize that beams are subject to tension on one side and compression on the other; recognize that flexibility is important in some structures) • infer how the stability of a model structure will be affected by changes in the distribution of mass within the structure and by changes in the design of its foundation (e.g., infer how the stability of a structure will be affected by increasing the width of its foundation) • devise and use methods of testing the strength and flexibility of materials used in a structure (e.g., measure deformation under load) • identify points in a structure where flexible or fixed joints are required, and evaluate the appropriateness of different types of joints for the particular application (e.g., fixed jointing by welding, gluing or nailing; hinged jointing by use of pins or flexible materials) • compare structural properties of different materials, including natural materials and synthetics • demonstrate and describe methods to increase the strength of materials through changes in design (e.g., corrugation of surfaces, lamination of adjacent members, changing the shape of components, changing the method of fastening) • identify environmental factors that may affect the stability and safety of a structure, and describe how these factors are taken into account (e.g., recognize that snow load, wind load and soil characteristics need to be taken into account in building designs; describe example design adaptations used in earthquake- prone regions) • analyze and evaluate a technological design or process on the basis of identified criteria, such as costs, benefits, safety and potential impact on the environment Skill Outcomes (focus on problem solving) Students will: • identify practical problems (e.g., identify a problem related to the stability of a structure) • propose alternative solutions to a practical problem, select one, and develop a plan (e.g., propose an approach to increasing the stability of a structure) • formulate operational definitions of major variables and other aspects of their investigations (e.g., define flexibility of a component as the amount of deformation for a given load) Communication and Teamwork Students will: Work collaboratively on problems; and use appropriate language and formats to communicate ideas, procedures and results • communicate questions, ideas, intentions, plans and results, using lists, notes in point form, sentences, data tables, graphs, drawings, oral language and other means (e.g., produce a work plan, in cooperation with other team members, that identifies criteria for selecting materials and evaluating designs) • work cooperatively with team members to develop and carry out a plan, and troubleshoot problems as they arise Language Arts Students will: Reflect on own observations and experiences to understand and develop texts. Identify and use visual and textual cues, such as numbers, bullets, and words that signal organization patterns in texts, to enhance understanding of ideas and information. Use note-taking, outlining or representing to summarize important ideas and information in texts. Plan and organize data collection based on instructions, explanations and pre-established parameters. Organize ideas and information by selecting or developing categories appropriate to a particular topic and purpose. Produce texts with well-developed and well-linked ideas and sections. Reflect on ideas and information to form own opinions with evidence to support them. Communicate ideas and information in a variety of texts, such as reports, etc. Use appropriate visual, print and/or other media effectively to inform and engage audience. Identify strengths and areas for improvement in personal research skills. Identify particular content features that enhance the effectiveness of published texts. Use paragraphs, appropriately, to organize narrative and expository texts. Identify how the format of documents enhances the presentation of content. Clarify and support ideas or opinions with details, visuals, and media techniques. Ask questions or make comments that elicit additional information; probe different aspects of ideas, and clarify understanding. Take responsibility for assuming a variety of roles in a group, depending on changing contexts and needs. Contribute ideas, knowledge and questions to establish an information base for research or investigations. Evaluate group process and personal contributions according to pre-established criteria to determine strengths and areas for improvement. Math Students will: Estimate and calculate percentages Read and write numbers to any number of decimal places Formulate questions for investigation from real-world context Materials You can use as much of all of these materials as you want. Pricing: 1 strand of spaghetti = $90.10 1 hot glue stick = $110.99 1 bottle of white glue = $605.78 1 metal hook = $199.99 String (per cm) = $25.66 Rules · The mass of the bridge must not exceed 750 g. · The deck of the bridge must be at least 50 mm wide over its entire length. · The bridge must be 60 cm long. · The bridge must be built without any attachments between the two support points, which are 50 cm apart. · The bridge must be supported at these points. · A one- or two-cm hook or eye must be attached at the centre of the bridge. · This hook will be used to hang a two-kg load in order to measure the bridge’s resistance. · The lightest bridge that is able to support the 2-kg load will be declared the winner. Procedure · Students will start with a journal, which will be written in 2 min. at the beginning and end of class. Everything is put in journal → diagrams, daily notes, materials, hypothesis, etc. · Each student will be given a job → General Manager – leader Accountant – record information Supplier – Gathers supplies · Each team will have a turn to measure the resistance of its bridge. · The organizing committee will provide the support points on which the bridges will rest. · All the bridges will be evaluated on the same support points. · The lightest bridge that is able to support the two-kg load will be declared the winner. Materials for organizing the challenge · 1 scale accurate to the gram · 1 tape measure · wooden supports for the bridges · 1 two-kg mass · 1 small wooden plaque to attach the hook · 1 hook or eye with a one to two-cm centre · 1 table to record results Note : For the sake of consistency, the organizing committee supplied the plaques and hooks at the regional challenge. The plaques were handed out before participants began building their bridges. We suggest that you provide these parts so that they are the same for everyone. Warning Epoxy glue can be toxic. Long-term exposure to the fumes can cause dizziness and nausea. If participants carry out this activity in class, the room should be well ventilated. We suggest that you carry out the activity in stages, so that participants aren’t exposed to the fumes for too long. Competition area Divide the area in which the activity will take place in two. One part will serve as the inspection and waiting area, while the other will be the bridge testing area. Preparing the competition area is easy. You must have two supports on which to rest the bridges and be able to hang a load from the bottom of the bridges. You can either build two solid wooden frames or use two desks. If you decide to use desks, make sure that the distance between the desks (50 cm) is the same for each team. Also, be sure to indicate the area on the desk (five cm) where participants can rest their bridges. Inspection Inspect the bridges before the competition. Begin by measuring the length. Then, weigh each bridge and record the mass in the designated table. Be sure that the scale is very accurate, since the differences may be minimal.