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Housing a business temporarily in response to a local natural disaster is an authentic technological context.

Our advice is to focus on the problem that the design brief poses. Leave outcomes as open-ended as possible to maximise creativity and engagement, rather than describing what it is you wish students to do.

A contextualised authentic technological issue, is a real problem that can be solved using technological processes – designing and developing solutions. It is in a context (building uses) that is familiar to students and that they have some ownership in. This ensures students are engaging fully in the problem solving process because it is meaningful and real to them.

The problem of relocating retail or cafe businesses post earthquake was an authentic technological issue during recent earthquakes. The context is spatial design in a retail or cafe business, and what you are maybe intending for the students to consider, is alternative spatial design in a more confined space?

The design brief you set, should inspire the students to investigate the issue. Directly connecting the issue/need/problem back to the real people who face these issues in your community is a great way to achieve this engagement. Students are then more likely to develop their creativity and technology capability so they can contribute authentically and help to solve the issues these people face.

A suggestion for a design brief for level 6, could be something like:

Issue: Our local town has 22 retail stores and six cafés. Should a natural disaster happen in our town, the businesses, their owners and their whānau would suffer hardship if they could not re-open quickly. The local council and individual business owners would appreciate support from you to suggest solutions that they could have in place should another natural disaster occur. Local councils and business owners are usually very happy to come into schools and discuss these issues, sometimes offering collaboration as a key stakeholder.

Context: Temporary structures such as shipping containers, and kitset garages are often solutions for temporary business premises when natural disasters happen.

Design brief conceptual statement: Select a local business to investigate and understand what their unique needs would be in being able to quickly relocate to a temporary structure to resume trading in the event of a natural disaster.

Specifications:

• Space – there is a limit of total available space of 24 square metres, 6 x 4 m (x amount - could be a shipping container size) for each business.
• Time – there are 6 weeks available to achieve a completed design outcome
• Budget – each business has a grant of $5000 for refurbishment and relocation
• Resources: Christchurch’s container mall and Rangiora town centre rebuild case study.

All meringues contain the same basic ingredients. These are egg white, sugar, and some sort of stabiliser.

• In a basic meringue, the ingredients are whisked together.
• In Italian meringue the sugar is heated to a syrup first.
• In Swiss meringue the whisking is done over a basin of water and heat.

In scientific terms, meringue is a foam – an aerated watery liquid. The constituent parts of a meringue recipe all have a role to play in the formation of the structure of the foam.

Egg whites

Egg whites are 90% water. The remainder is almost all protein, with trace amounts of minerals and vitamins. The specific protein in egg whites is called albumin. All proteins are made up of long chain amino acids. The sequencing of the amino acids in a protein cause it to wind up on itself, like a ball of yarn. Some amino acids are hydrophobic (water hating) and some are hydrophilic (water loving).

In egg white, the hydrophobic amino acids are tucked away on the inside of the ‘ball’ and the hydrophilic ones surround them and face out. When egg white is whisked, air is introduced to make a foam. At the same time, the mechanical action of whisking causes some of the proteins to unravel or unfurl; this is called denaturing. As the proteins denature, they take up more space – rather like a ball of yarn unravelling.

Denaturing exposes some of the hydrophobic amino acids, which will move towards the introduced air bubbles (and away from the water that is in egg white). As the air bubbles become coated in proteins, the hydrophobic amino acids interact and form nets, which prevents the bubbles from popping and helps the foam to become more stable.

The process of denaturing may also be chemically assisted by the addition of an acid such as lemon juice, vinegar, or cream of tartar. These acids help to increase the amount of air the denatured proteins can hold – making the meringue fluffier and lighter. They do this by donating positively-charged hydrogen ions to the egg white’s negatively-charged protein strands, which neutralises the meringue. This reduces the time it takes for the amino acids to denature and allows more air to be incorporated. The acids help to stabilise the foam structure. The acids also prevent too many proteins from linking together, so that the protein nets do not become too tight. This phenomenon is sometimes observed if meringue is over-whisked. Too much whisking can cause the mixture to split into a grainy solid and a runny liquid. This happens when too many proteins join together and form a net that is so tight that it starts to squeeze the water out of the egg white.

The solution to over-whisking is to add another egg-white, so that there are more unattached protein molecules introduced into the mixture. Another way of stabilising the mixture is to whisk the egg whites in a copper bowl. Small quantities of positively charged copper ions from the copper molecules in the bowl will also prevent too many protein molecules from linking together.

Salt may also be added to a meringue once the egg whites have been whisked. If it is added during whisking, it quickly separates into its component parts of sodium and chlorine. The sodium and chlorine can bond to the egg white proteins, which leaves less potential bonding sites for other egg white proteins to use in order to form long chains. Adding salt after the meringue has formed ensures that all of the available protein chains have safely bonded together.

Temperature also plays a role. A cold egg makes it easier to separate the egg white from the yolk and will be more stable. However, room-temperature eggs will result in a lighter meringue and turn into meringue faster.

Speed is important; the faster the whisking, the more quickly the proteins will be denatured and the more readily a meringue will form.

Sugar

The addition of sugar to the whisked egg whites helps to create a thick and glossy foam that remains aerated even when whisking stops. Sugar helps more of the protein molecules to gather on the surface of the air bubble, making the structure more stable. In other words, it acts as a scaffold to support the foam.

Sugar, as sucrose, is a molecule made up of fructose and glucose. Since glucose is highly soluble, it dissolves in the foam and will surround the air bubbles. The smaller the physical size of the sugar particles or grains, the quicker it will dissolve and coat the foam structure. Therefore, icing sugar stabilises more quickly than caster sugar. The sooner the sugar is added to the mixture, the denser and firmer the meringue will be. When sugar is added to the egg whites early in the whisking process, there is plenty of water, which helps to turn the sugar into a thick syrup. The syrup helps to provide bulk and stability to the network of bubbles in the foam but also weighs the meringue down-
reducing the overall volume.

Italian meringue

In Italian meringue the sugar syrup is heated before adding it to the egg white foam. Heavy syrup does not create light, thin bubble walls, so the meringue is denser. Sugar molecules also obstruct proteins which are trying to unfurl and denature, so the meringue will be slow to whip.

Swiss meringue

In Swiss meringue the sugar is added late in the whisking process. Adding sugar when the meringue is already formed will still create a thick syrup, but one which bulks up bubble walls that have already been built. This means there is no loss of volume. In a hot process meringue such as Italian or Swiss meringue, the type of protein in the egg white is also important in the stabilisation process. The main type of protein in an egg white is ovalbumin. However, there is also ovomucin and lysozyme. Each of these has a different level of sensitivity to heat. With the addition of heat, ovalbumin is finally denatured and that adds a lot of stability. Sugar also dissolves more efficiently into warm water, so the sugar syrup created in a hot process meringue is stronger too.

In Swiss meringue, the mixture is heated so much that the egg whites actually pasteurise and the finished product is stable at room temperature. During cooking water evaporates at high temperature. This triggers a reaction in sugar causing it to caramelise and become solid. When the whisked-up egg white is cooked, the proteins becomes completely denatured, meaning they cannot return to their former shape. This is what makes meringue solid.

References

• Devil's food kitchen, Food science: Meringue
• Fine Dining lovers, The science of meringue
• Smithsonian Magazine, Meringue chemistry: The secrets of fluff
• The Conversation, Kitchen science: The chemistry behind amazing meringue and perfect cappuccino
• Medium, The science behind: Meringue
• Let's talk science, Meringue: The science behind a wonderfully fluffy dessert

Planning learning programmes for courses covering the revised digital content is a need for teachers that has been well-supported by the digital technologies supports, particularly in the Digital technologies support section.

There is a great example shown in a teaching snapshot of how one school addressed the need for girls to be engaged in computer science (Technological area, computational thinking for digital technologies).

There are other teaching and student snapshots that contain resources produced to meet the need for delivery of digital technologies such as: Local curriculum design in technology: Tēnei au.

Modular field camp system and Excelling in electronics, although pre-2017 revision, are resources that could also be useful.

The webinar on the revised technology learning area has suggested examples of a coherent technology learning programme in years 7 - 8 and years 9 – 10. See the drop down menus at the bottom of the page: Revised technology learning area.

The Tūrangawaewae rauemi pīkau resource for years 9 – 10 on Kia Takatū ā-Matihiko might also assist in planning a programme of learning. You can find this on the Rauemi pikau, resource toolkit page on the Kia Takatū ā-Matihiko site.

The overview of skills you could use for a 10 week digital technologies course are contained in the progress outcomes, the significant learning steps that build student digital capability each year.

See:

• Computational thinking for digital technologies
• Designing and developing digital outcomes

Any programme of learning should be designed to meet the unique needs of your students, your location, community, and whānau expectations. See the Leading local curriculum design in the revised technology learning area guide for further support.

This is a common question that is a good starter for team discussions when designing local curriculum to support students' critically thinking about the world around them. The technological systems component of the technological knowledge strand is essential for students to understand how and why systems operate in the way they do.

Technology is about transformation of energy, information, and materials, intervening by design. The technological systems component looks more closely into what this transformation is and how we can design systems to be efficient, equitable, and inclusive. A technological system is a set of components or parts that serve to perform a function to make life easier or simpler. A system transforms an input into an output.

Your glue bottle versus glue stick is a great example of a technological outcome. A glue stick is also a technological system. This is because it transforms the input (human energy) by a twisting action of the simple, hidden, thread mechanism that pushes out the glue (the output).

Sometimes we can see the process part of the system with our own eyes. For example, the bevel gear in a hand operated egg whisk or the pivot part of the lever system in scissors. But mostly the process part is hidden, like in a door lever mechanism. This hidden stage or the process part, is referred to as the black box of a system (see achievement objectives level 2 - approximately year 3 and up).

Yes, mechanical systems like scissors, whisks, doors, and engines are all technological systems. Anything which performs a function and changes/transforms energy as it does its job, is a technological system. It's lots of fun to have a quiz with students to look at everyday technological outcomes around them and discuss which are systems and which are products, and which are both. For an example of teaching and learning on technological systems in years 1–3 see the snapshot: Exploring technological systems and computational thinking using household appliances.

The only expectation of the standard affected by a delay in not receiving the actual final fabric is whether the complex applied design enhances the final product (in this case a garment.) (AS91621 Explanatory Note 3)

The standard expects the student to interpret and apply a complex design to a specified product.

This includes how students have trialled and decided upon the equipment and materials for the applied design and how they use complex techniques (while complying with health and safety regulations) to create the (applied) design.

Due to the delays with COVID 19 in 2020, if the student has evidence of the complex design being trialled and applied to a similar fabric and can explain how this would enhance the final product, the standard could be considered as met in 2020.

The consensus of teachers and industry professionals, including chefs who are teachers, is that each student should be developing the HACCP plan for their own food product that they had developed as a prototype/item being assessed by the standard.

That the group are then producing multiple dishes in a restaurant situation and will require multiple HACCP schedules seems to be a separate issue.

No one could find a justification for requiring every student to develop multiple HACCP schedules in order to cover all the menu options. Each student could produce one food product (developed through prototyping) and HACCP plan. In order to run a restaurant scenario, everyone shares recipes and HACCP plans. This is a situation that the assessor needs to manage carefully and be very mindful not to over assess the students.

It can be difficult to meet the audience interactivity component of the standard using only a website. By choosing a website, with only basic navigation, takes away the ability of the viewer to control their own movement throughout the site. The website becomes essentially two dimensional (although movement is possible). The student designer is expected to consider and plan for how the viewer could interact with the exhibition; this could include the ergonomics of the viewer in relation to the screen, whether they are sitting or standing, and for example, what choices they can make about within the website.

Yes the standard 91611 is still valid. See NZQA resources exemplars and commentary (PDF, 1.8MB). The standard can be round on NZQA here.It is currently available for assessment and is due to be reviewed at the end of 2020.

The standards mentioned are all currently available on the NZQA site for assessment by education organisations who have consent to assess.

If this applies, please be aware the National Certificate in Electronics Technology for Level 2 (of which most of the standards listed above comprise) is expiring at the end of the year. The last date for assessment is 31st December 2020.

See NZQA electronics technology for further details. There is no information available at this point, as to whether the unit standards will be available after this time.