Selecting and solving teaching materials problems

Units and symbols. Select, interpret, and use units and symbols. Emphasize the use of units whenever applicable. Develop a habit of using appropriate units and symbols yourself at all times.

Constraints. Teach students to look for the words only, must, neglect, or assume to help identify the constraints.

Active / Execution phase
The following are the general procedural steps in Execution phase:
Step one
Selection of the Problem and Presentation of the Problem :A number of problems are confronted by the students in the class or outside. They are made to select a problem as per their capacity and interest.
Each student is made to feel responsible for presenting the problem in front of the teacher and class as per his insight. The students are free to give their suggestions on the problem. Diagnose the situation so that your focus is on the problem .
Step two. Generation of alternative solutions: All the facts related to problem are collected either by a students or group. As a number of facts will be collected, it will help the students to keep the most pertinent facts and discard rest.
Step three. Generate alternative solutions: Postpone the selection of one solution until several alternatives have been proposed. Having a standard with which to compare the characteristics of the final solution is not the same as defining the desired outcome. Considering multiple alternatives can significantly enhance the value of final solution. Many alternative solutions should be generated before evaluating any of them. A common mistake in problem solving is that alternatives are evaluated as they are proposed, so the first desired solution is chosen, even if it’s not the best fit.
Step four. Evaluate and select an alternative: Skilled problem solvers use a series of considerations when selecting the best alternative. They consider the extent to which:

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  A particular alternative will solve the problem without causing other unanticipated problems.
  
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  All the individuals involved will accept the alternative.
  
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  Implementation of the alternative is likely.
  
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  The alternative fits within the organizational constraints.