Junior School: Choosing Materials for a Design Brief

Junior School: Choosing Materials for a Design Brief

A material is suitable when its properties fit a particular job. The cheapest option can fail the brief, while the strongest-looking option may need a process the class is not allowed to use. In this original paper-design activity, compare supplied material cards before recommending a tabletop label holder. All properties and prices below are fictional exercise data, not supplier quotations or results of a real test.

Teacher-use draft for junior school, intended for learners ready to compare constraints and multiply costs. Exact grade, strand and term placement needs subject-teacher review. Work from the cards and drawings on paper; no cutting, heating, drilling or material testing is required.

The complete product brief

The fictional Cedar Display Group needs six identical holders for a dry indoor display. Each must keep one paper name label upright, accept a pencil-written label, have smooth prepared edges and use only a teacher-supplied blank plus a prepared attachment tab. The total materials allowance is KSh 180. Each holder uses one blank and one tab; each tab costs KSh 2. There is no delivery charge or other cost in this exercise. There is no requirement to carry a load or contact food.

The group wants the lowest total cost among options that meet every essential condition. A low cost cannot cancel an essential failure. The cards describe complete prepared blanks; they do not claim that every material of that general type behaves identically.

Screen the options before ranking price

Card A costs (8 + 2) × 6 = KSh 60, leaving KSh 120. Nevertheless, it fails the upright requirement. A statement that A is best because it saves most money ignores the product’s purpose. Card C would cost (30 + 2) × 6 = KSh 192, already KSh 12 over budget, and its preparation process is not permitted. Neither additional supervision nor a cheaper tab is supplied as a way to change that process limit.

Card D would have a recorded purchase cost of only 6 × 2 = KSh 12, but missing evidence is not a pass. Its free price does not establish condition, smooth edges or suitability. Write “not established from this card” rather than “unsafe” or “safe”: either certainty would exceed the record. A teacher would need an appropriate inspection before considering a real recovered material.

Card B meets every stipulated dry-display condition. Its six blanks cost 6 × 18 = KSh 108; six tabs cost KSh 12; total cost is KSh 120. The remaining allowance is 180 − 120 = KSh 60. The recommendation is therefore B within this particular brief. This is a comparison of supplied evidence, not a certification that the material is safe for every classroom product.

A complete model recommendation

“I recommend the prepared firm card, B, for the six dry-display holders. It meets the recorded upright, label and smooth-edge conditions without an excluded preparation process. Including tabs, it costs KSh 120, within the KSh 180 allowance. A fails the upright condition; C exceeds the allowance and needs excluded equipment; D has unresolved checks. B should not be carried into a damp-display brief unchanged because its own card limits it to dry use.”

Notice the order: name the choice, connect it to the requirements, calculate the whole quantity and state a limitation. “Card is strong” is too general. Strength, stiffness, absorbency and ease of marking concern different properties; this record supplies only the particular behaviours needed for this decision.

Independent task: change the environment

The same group now needs six holders for a damp display area. The allowance stays KSh 180 and all earlier conditions remain, with one extra essential condition: the blank must retain its form under the supplied damp-condition check. B now fails that condition. A new card E is supplied: a smooth, preprepared coated-card blank at KSh 28, compatible with the KSh 2 tab and label, and recorded as meeting both the upright and damp-condition checks. No new fabrication is needed.

1. Choose an option and show the six-holder total.
2. Explain why the earlier B recommendation changes even though B’s price has not changed.
3. If the allowance is reduced to KSh 150, can any fully supported option satisfy the revised brief?

Checked answers and review

E costs (28 + 2) × 6 = KSh 180, exactly the allowance, so it qualifies under the supplied cards. B is now excluded by the damp-condition requirement, not by price. At KSh 150, E exceeds the allowance by KSh 30 and no fully supported option remains. Report the conflict and ask the fictional organiser to revise the allowance, quantity or conditions. Do not invent a property for D or propose an excluded process to make the numbers fit.

Review a response against four criteria: it uses every essential condition; separates a missing check from a failed check; includes both blanks and tabs for all six holders; and explains how a changed requirement changes the decision. Award credit for the reasoning rather than the severity of rejection. A useful next step for an incomplete answer is to highlight the exact condition it omitted.

Reference for the selection method: The Open University on materials selection explains screening materials against a product specification and service conditions. The classroom cards, costs and answers here are original; they are not extracted supplier data.