Approaches to teaching the content 

Students might not have come across the different software development methodologies as they usually work alone. A few activities are detailed which give practical examples of how some of the processes work. 

As suggested in one of the activities, you could invite in a speaker from the industry to talk about how they work and deal with their software development processes; this would be a valuable insight for students to have.

Understand the waterfall lifecycle, agile methodologies, extreme programming, the spiral model and rapid application development 

The relative merits and drawbacks of different methodologies and when they might be used

Waterfall model (systems life cycle) – This process is sequential and goes through the phases of conception, initiation, analysis, design, construction, testing, implementation and maintenance. It was first invented for hardware manufacture, but then was adapted for software development. 

Agile methodologies (agile software development) are a way of developing software in incremental parts called ‘sprints’ that typically last around three weeks. Therefore a website may be launched and then every three weeks new features are added. This helps to continually refine the requirements specification to the customer’s wants and needs. 

A good video that explains agile development can be found on YouTube.

Extreme programming is a type of agile software development process, but it puts emphasis on pair programming, code review (part of pair programming) and unit testing.  

The spiral model combines the idea of iterative development with the systematic aspects of the waterfall model. The spiral model has four phases (identification, design, build and evaluation/risk analysis). Each time the cycle is done the customer supplies feedback and risk analysis looks at the possibility of overruns of time/money requirements.  

Rapid application development is a software development process that relies heavily on programming and does not go into too much detail/time on requirements or planning. This needs heavy involvement from the customer to continually review prototypes to suggest improvements. 

Writing and following algorithms

Algorithms are some of the most fundamental parts of most programs, especially where there is a lot of data involved. Algorithms are a set of rules to be followed in a problem-solving operation, so it is important that our ‘rules’ are appropriate for what we are trying to achieve. 

The CSfieldguide website has a very good introductory video complete with activities and some in-depth information on types of sorting algorithm. 

Some good activities for practically illustrating different algorithms are given at the end of the teacher’s guide. 

The Teach-ICT.com website covers Linear search, Binary search, Merging, Sorting, Insertion sort, Quicksort.

There is also an interesting set of animations showing how fast different sorting algorithms are in comparison to each other.

Common misconceptions or difficulties students may have 

Students may have difficulties remembering which software development strategy is which. Diagrams will usually aid with this. The Tutorialspoint.com website helps as it gives a clear definition of each process with an accompanying diagram.

Conceptual links to other areas of the specification – useful ways to approach this topic to set students up for topics later in the course 

Students will gain experience with going through the stages of a project for their controlled assessment, but won’t have exposure to working in a team environment for this.