A team must design a cooler keeping a can below 10 C for two hours. They have $8, only supply-bin materials, and until Friday. Which requirement states what the cooler must achieve?

A team designs a bike light that shines 30 m ahead, stays lit 4 hours, and clips to any handlebar. The school says spend no more than $12. Which requirement limits how the team may build it?

A class builds a filter that must clear 2 L of pond water in 10 minutes and leave no visible grit, using only kit sand, gravel and cotton. Which statement restricts the team, not the finished filter?

A team designs a mini greenhouse that must keep soil above 18 C overnight. The kit is one shoebox, plastic sheet and tape, and it is due Thursday. Which requirement states what the greenhouse must achieve?

A student designs a grabber that picks a 200 g can off a high shelf. It must be under 60 cm long, cost under $5, and use no motors. Which requirement describes the tool's job?

A team designs a lap tray that holds a lunch tray steady, clips on in five seconds, and supports 3 kg. The school allows only materials already in the makerspace. Which requirement limits the team's work?

A club builds a birdhouse that must keep chicks dry in heavy rain. The club has $10, scrap plywood only, and two afternoons. Which requirement is about the birdhouse itself, not the club's resources?

A group designs a solar oven that must reach 70 C in full sun within 30 minutes. Only cardboard, foil and plastic wrap are allowed, the budget is $6, and it is due Friday. Which statement is the oven's goal?

Students design a doorway flood barrier that blocks water 20 cm deep for one hour and can be set up by one adult. The town forbids drilling into the sidewalk. Which requirement is a constraint, not a criterion?

A class designs a compost bin that must hold 40 L, keep rain out, and turn easily for one student. It must sit inside a 1 m square of ground. Which requirement is a constraint, not a criterion?

A team writes the goal 'Our model tower should be tall and steady.' Their teacher asks for a version a test could settle. Which restatement does that?

A group's goal reads 'The lunch bag should keep food cold.' Which version of that goal could a thermometer and a clock settle?

A team's water-rocket goal says 'It should fly far and land near the target.' Which wording could a tape measure decide?

Two teams must judge the same hand-washing station by one goal. Which goal would both teams score the same way?

A team wants a wall panel that makes a classroom quieter. Which version of that goal states a result a meter can check?

A team's wind turbine goal reads 'It should make useful electricity.' Which restatement gives a number the team can measure with a voltmeter and a fan?

A team plans an automatic pet feeder and writes 'It should feed the cat reliably.' Which restatement could a week-long trial settle?

A garden team writes 'Our seed dispenser should work well.' Which restatement turns that into something a trial run can settle?

A shade sail team has 4 m of fabric, a $60 budget, two weeks, and a rule that nothing attaches to the school wall. Their plan anchors one corner with a bracket screwed into the building. Which limit does it break?

A phone-stand team may use recycled cardboard only, must finish in one 50-minute class, may not use glue guns, and must stay under 15 cm tall. They plan to laser-cut acrylic sheet. Which limit does that plan break?

A rover team must stay under 500 g, spend under $25, use one 1.5 V battery, and finish by Monday. Their build weighs 700 g. Which stated limit does the build run into?

A greenhouse team has $25 for materials, one week, a 2 m by 1 m plot, and a ban on power tools. Their parts list totals $34. Which stated limit does the parts list run into?

A team may use two class periods, $15, a 40 cm windowsill, and no open flame. Their seedling tray measures 45 cm across. Which stated limit does the tray run into?

A food-warmer team works under a $20 budget, a two-day deadline, a rule that no heating element may be exposed, and a 30 cm size limit. Their design leaves the coil uncovered. Which limit does it break?

A model car team may use one 1.5 V battery, $10, recycled wheels, and three afternoons. Their design runs on a 3 V battery pack for more speed. Which stated limit does it break?

A team has three 45-minute sessions, $30, kit materials only, and a 2 kg mass limit. Their plan needs 20 hours of glue drying between steps. Which stated limit does that plan run into?

A principal asks a class to 'do something about the noisy hallway.' Before designing, the class must state the problem precisely. Which statement defines the design problem well enough to work on?

A teacher asks students to 'help people remember their homework.' Which statement turns that request into a design problem the class can start on?

A groundskeeper asks a class to 'fix the muddy path across the field.' Which statement defines that as a design problem?

A class is told 'our room gets too hot in the afternoon.' Which statement states the problem precisely enough to begin designing?

A gardening club says 'the school garden dies over the two-week break.' Which statement turns that into a defined design problem?

A teacher says 'protect the egg when it falls.' Before building, the class must define the problem. Which statement does that well enough to design against?

Students are asked to 'make the bike rack better.' Which restatement defines a design problem a team could start work on this week?

A cafeteria manager says 'too much food gets thrown away.' Which statement defines a design problem precisely enough to test a solution against?

A tray carrier must hold 6 trays, fit a 50 cm shelf, cost under $20, and have no sharp edges. One team's 46 cm metal frame holds 6, costs $14, and has bare cut edges. Which requirement fails?

A helmet liner must pass a drop test, mass under 150 g, be machine washable, and cost under $12. A team's liner passes, masses 120 g, costs $9, and uses a wash-dissolving glue. Which requirement fails?

A solar charger must give 5 V, charge in under 4 hours, mass under 400 g, and cost under $30. A team's charger gives 5 V, masses 380 g, costs $22, and takes 6 hours. Which requirement fails?

A rain gauge stand must be 1 m tall, survive a 60 km/h gust, cost under $18, and avoid concrete. One stand is 0.7 m tall, costs $25, uses concrete, but survived the gust. Which requirement does it meet?

A planter must hold 5 L, fit a 30 cm rail, have drainage holes, and cost under $10. One holds 5 L, is 28 cm wide, costs $8, but has a sealed base. Which change meets the brief?

A book cart must carry 20 kg, pass a 75 cm doorway, have locking wheels, and cost under $50. A team's cart carries 20 kg, is 70 cm wide, costs $45, and rolls freely. Which requirement fails?