Brick-compatible mechanisms
Gear Ratio Demonstrator
Turn one crank and compare how gear size changes output speed, direction, and turning force.
- Level
- Beginner
- Time
- 45-60 min
- Cost
- $0-$10
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Brick-compatible mechanisms
Compound Gear Train
Stack two gear reductions on a shared middle axle to create a large speed change in a compact frame.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Cardboard builds
Cardboard Arcade Button
Build a large springy push button that closes a foil contact and can trigger a low-voltage game input or continuity test.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$5
Household engineering
Rubber Band Car
Store energy in a twisted rubber band, release it through the drive axle, and tune a lightweight car for distance.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$8
Classroom challenges
Pulley Elevator
Raise a small platform with fixed and movable pulleys, then compare input force, rope travel, and mechanical advantage.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$8
Robotics/electronics
Simple Motorized Fan
Build a guarded low-voltage fan, switch it with a transistor, and compare airflow at two safe blade pitches.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$12
Coding/game projects
Scratch Arcade Game
Build a keyboard-controlled collecting game with falling objects, lives, score, speed progression, and a clear restart loop.
- Level
- Beginner
- Time
- 60-90 min
- Cost
- $0
Brick-compatible mechanisms
Idler Gear Direction Reverser
Add a middle idler gear to change output direction without changing the ideal speed ratio.
- Level
- Beginner
- Time
- 40-60 min
- Cost
- $0-$10
Brick-compatible mechanisms
Bevel Gear 90-Degree Drive
Turn motion around a right-angle corner with two bevel gears and a rigid three-dimensional frame.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$18
Brick-compatible mechanisms
Worm Gear Winch
Use a worm and wheel to lift a small load slowly with a large reduction and strong resistance to back-driving.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$18
Brick-compatible mechanisms
Rack-and-Pinion Slider
Convert turning motion into straight-line travel with a pinion gear, guided rack, and visible distance scale.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$15
Brick-compatible mechanisms
Crank-Slider Piston
Turn continuous crank rotation into repeating piston motion with a rigid connecting rod and guided slider.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Brick-compatible mechanisms
Scotch Yoke Oscillator
Drive a slotted yoke with an offset crank pin to create compact sinusoidal back-and-forth motion.
- Level
- Intermediate
- Time
- 60-85 min
- Cost
- $0-$15
Brick-compatible mechanisms
Four-Bar Rocker
Connect four links into a crank-rocker mechanism that turns continuous input into a controlled swinging output.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Brick-compatible mechanisms
Parallel-Motion Linkage
Build a parallelogram linkage that keeps an output platform nearly level as it moves through an arc.
- Level
- Intermediate
- Time
- 55-80 min
- Cost
- $0-$15
Brick-compatible mechanisms
Pantograph Drawing Arm
Trace a simple shape and copy it at a different scale with four linked bars and carefully spaced pivots.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Brick-compatible mechanisms
Cam-and-Follower Lift
Turn a shaped cam to lift and lower a guided follower with a repeatable dwell and rise pattern.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$12
Brick-compatible mechanisms
Eccentric Cam Shaker
Offset a rotating mass to create controlled vibration and compare how speed and eccentricity change shaking.
- Level
- Beginner
- Time
- 40-60 min
- Cost
- $0-$10
Brick-compatible mechanisms
Geneva Intermittent Drive
Convert continuous input rotation into indexed output steps with a drive pin, locking disk, and slotted wheel.
- Level
- Advanced
- Time
- 90-150 min
- Cost
- $0-$20
Brick-compatible mechanisms
Ratchet-and-Pawl Winch
Wind a small lifting drum in one direction while a pawl catches each ratchet tooth to prevent rollback.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Brick-compatible mechanisms
One-Way Clutch
Build a roller-style clutch that transmits rotation one way and freewheels in the other direction.
- Level
- Advanced
- Time
- 90-130 min
- Cost
- $0-$20
Brick-compatible mechanisms
Torque-Limiting Slip Clutch
Protect a mechanism by letting two friction disks slip when output resistance exceeds an adjustable limit.
- Level
- Advanced
- Time
- 80-120 min
- Cost
- $0-$20
Brick-compatible mechanisms
Open Differential
Split one input between two outputs that can rotate at different speeds while preserving their average speed.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Two-Speed Manual Gearbox
Select between a fast output and a high-reduction output with two permanent gear pairs and a sliding engagement collar.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Reversing Gearbox
Switch one output between forward, neutral, and reverse by sliding an idler gear between two controlled mesh paths.
- Level
- Advanced
- Time
- 100-150 min
- Cost
- $0-$22
Brick-compatible mechanisms
Belt Drive Transmission
Link two distant pulleys with an elastic belt and compare ratio, tension, slip, and direction.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$12
Brick-compatible mechanisms
Chain Drive Transmission
Transmit rotation across a wide gap with sprockets and a linked chain that keeps a positive tooth-to-link relationship.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$18
Brick-compatible mechanisms
Block-and-Tackle Hoist
Route one rope through fixed and moving pulleys to trade longer pulling distance for lower ideal lifting force.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Brick-compatible mechanisms
Universal Joint
Transmit rotation between shafts meeting at an angle with two yokes and a central cross.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$18
Brick-compatible mechanisms
Oldham Coupling
Connect parallel but offset shafts with two slotted hubs and a floating middle disk that slides in perpendicular directions.
- Level
- Advanced
- Time
- 90-130 min
- Cost
- $0-$20
Brick-compatible mechanisms
Flexible Beam Coupling
Connect slightly misaligned shafts with a torsionally flexible beam element and compare compliance with backlash.
- Level
- Intermediate
- Time
- 55-80 min
- Cost
- $0-$15
Brick-compatible mechanisms
Lead-Screw Linear Actuator
Rotate a threaded shaft to move a guided carriage precisely along a straight path.
- Level
- Intermediate
- Time
- 70-100 min
- Cost
- $0-$18
Brick-compatible mechanisms
Toggle Clamp
Push a linkage near straight alignment to create high clamping force and a stable over-center locked position.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Brick-compatible mechanisms
Over-Center Latch
Pull two panels together with a hook-and-link latch that becomes stable after its pivot passes center.
- Level
- Intermediate
- Time
- 55-80 min
- Cost
- $0-$12
Brick-compatible mechanisms
Parallel-Jaw Gripper
Synchronize two jaws so their gripping faces stay parallel while moving toward the center.
- Level
- Intermediate
- Time
- 70-100 min
- Cost
- $0-$18
Brick-compatible mechanisms
Linkage Grabber Arm
Extend hand motion through a long two-jaw linkage to pick up lightweight objects from a distance.
- Level
- Intermediate
- Time
- 75-110 min
- Cost
- $0-$18
Brick-compatible mechanisms
Walking Beam Mechanism
Drive a rocking beam from a crank and transfer alternating lift between two ends.
- Level
- Intermediate
- Time
- 70-100 min
- Cost
- $0-$18
Brick-compatible mechanisms
Theo Jansen Leg Module
Coordinate several links around one crank to create a foot path with a flat walking phase and lifted return.
- Level
- Advanced
- Time
- 150-220 min
- Cost
- $0-$30
Brick-compatible mechanisms
Chebyshev Walking Linkage
Use a compact four-bar geometry to create an approximate straight foot path during part of each crank cycle.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Peaucellier Straight-Line Linkage
Construct an exact straight-line linkage from a rhombus and equal-length links, then trace its constrained output path.
- Level
- Advanced
- Time
- 150-240 min
- Cost
- $0-$28
Brick-compatible mechanisms
Rack Steering with Ackermann Approximation
Steer two front wheels with a rack so the inner wheel turns more sharply than the outer wheel in a curve.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Independent Suspension Module
Guide one wheel through vertical travel with upper and lower arms while the opposite side remains mostly still.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Escapement Mechanism
Release a driven wheel one tooth at a time with an oscillating anchor and a low-energy pendulum-like regulator.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Mechanical Counter
Advance a numbered wheel one step per input event and carry from ones to tens after a full revolution.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Mechanical AND Gate
Require two separate input levers to be active before a mechanical output slider can move.
- Level
- Advanced
- Time
- 90-140 min
- Cost
- $0-$20
Brick-compatible mechanisms
Bistable Flip-Flop Mechanism
Store one mechanical bit with an over-center lever that remains in either of two stable states after the input is removed.
- Level
- Advanced
- Time
- 90-140 min
- Cost
- $0-$20
Brick-compatible mechanisms
Low-Speed Centrifugal Governor
Raise two hinged masses as hand-driven speed increases, then use their height as a visible speed signal.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$25
Brick-compatible mechanisms
Flywheel Energy Smoother
Add rotational inertia to a crank-driven mechanism and compare speed variation, coast time, and starting effort.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$12
Brick-compatible mechanisms
Planetary Gearset
Arrange sun, planet, ring, and carrier elements on one axis to explore several ratios in a compact transmission.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0-$30
Brick-compatible mechanisms
Differential-Steer Rover Chassis
Control a rover by changing left and right wheel speeds, enabling straight travel, arcs, and turns in place.
- Level
- Intermediate
- Time
- 90-130 min
- Cost
- $0-$25
Cardboard builds
Cardboard Pinball Machine
Build a sloped tabletop game with a safe spring plunger, pivoting flippers, bumpers, lanes, and a repeatable scoring test.
- Level
- Intermediate
- Time
- 90-150 min
- Cost
- $0-$10
Cardboard builds
Cardboard Claw Machine
Guide a hand-controlled carriage over a prize bin, lower a string claw, close it, and lift lightweight objects.
- Level
- Advanced
- Time
- 150-240 min
- Cost
- $0-$15
Cardboard builds
Cardboard Foosball Table
Build a tabletop game with rotating player rods, contained ball motion, goals, and a fair playfield layout.
- Level
- Beginner
- Time
- 75-110 min
- Cost
- $0-$8
Cardboard builds
Cardboard Coin Sorter
Sort sample coins by diameter with a sloped track and a sequence of carefully measured openings.
- Level
- Beginner
- Time
- 55-80 min
- Cost
- $0-$5
Cardboard builds
Cardboard Marble Elevator
Lift marbles repeatedly with hand-cranked cups on a loop or rotating wheel and return them to a marble run.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$8
Cardboard builds
Hand-Crank Cardboard Automaton
Animate a small cardboard character with a hand crank, cam, follower, and guided moving scene element.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$8
Cardboard builds
Cardboard Periscope
Redirect a line of sight through a tall cardboard tube with two parallel mirrors set at 45 degrees.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$6
Cardboard builds
Cardboard Camera Obscura
Project an inverted outdoor scene onto tracing paper with a light-tight cardboard box and a tiny aperture.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$5
Cardboard builds
Water-Hydraulic Cardboard Robot Arm
Move a reinforced cardboard arm with paired water-filled syringes that transmit force and displacement through tubing.
- Level
- Advanced
- Time
- 150-240 min
- Cost
- $0-$18
Cardboard builds
Cardboard Wind Turbine
Build a guarded tabletop rotor and compare blade angle, area, and load using a household fan as a repeatable wind source.
- Level
- Intermediate
- Time
- 75-110 min
- Cost
- $0-$8
Cardboard builds
Cardboard Ferris Wheel
Build a hand-cranked wheel with hanging gondolas that remain upright as the rim turns.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$8
Cardboard builds
Cardboard Spirograph Drawing Machine
Roll a toothed cardboard gear inside a ring and trace repeating curves from different pen-hole positions.
- Level
- Intermediate
- Time
- 75-110 min
- Cost
- $0-$6
Cardboard builds
Cardboard Mechanical Hand
Pull string tendons through straw guides to bend segmented cardboard fingers and grasp lightweight objects.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$8
Cardboard builds
Cardboard Conveyor Belt
Move lightweight objects across a frame with two rollers, an endless paper belt, and adjustable tracking guides.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$10
Cardboard builds
Cardboard Vending Machine
Dispense one lightweight item per handle turn with a rotating pocket wheel, gravity feed, and delivery chute.
- Level
- Intermediate
- Time
- 100-160 min
- Cost
- $0-$10
Cardboard builds
Cardboard Combination Safe
Align three notched code wheels in sequence so a fence can drop and release a lightweight cardboard door bolt.
- Level
- Advanced
- Time
- 140-220 min
- Cost
- $0-$10
Cardboard builds
Cardboard Gearbox Display
Cut large visible cardboard gears and mount them in an open frame to demonstrate ratio, direction, idlers, and compound stages.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$8
Cardboard builds
Hand-Crank Cardboard Desk Fan
Spin lightweight paper blades through a guarded hand-crank transmission and compare blade pitch and gear ratio.
- Level
- Beginner
- Time
- 55-85 min
- Cost
- $0-$6
Cardboard builds
Cardboard Walking Creature
Coordinate two mirrored crank-driven leg pairs so a lightweight cardboard body steps forward across a high-friction surface.
- Level
- Advanced
- Time
- 150-240 min
- Cost
- $0-$12
Household engineering
Balloon-Powered Car
Use air escaping from a balloon through a straw nozzle to propel a lightweight car and compare nozzle size.
- Level
- Beginner
- Time
- 40-65 min
- Cost
- $0-$8
Household engineering
Paper Bridge Challenge
Fold one sheet of paper into a bridge that spans 20 cm and compare how cross-section shape changes load capacity.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$3
Household engineering
Paper Tower Challenge
Build the tallest freestanding tower from limited paper and tape, then evaluate buckling, base width, and bracing.
- Level
- Beginner
- Time
- 35-60 min
- Cost
- $0-$3
Household engineering
Straw Truss Bridge
Build two triangulated side trusses from straws and connect them into a bridge that carries a centered test load.
- Level
- Intermediate
- Time
- 75-110 min
- Cost
- $0-$8
Household engineering
Bottle-Cap Pulley Crane
Build a tabletop crane with a bottle-cap pulley, rotating boom, hand winch, and lightweight hook.
- Level
- Beginner
- Time
- 55-85 min
- Cost
- $0-$6
Household engineering
Clothespin Grabber
Extend a clothespin's squeeze action through lightweight arms and soft jaws to pick up small objects.
- Level
- Beginner
- Time
- 30-50 min
- Cost
- $0-$6
Household engineering
Craft-Stick Scissor Lift
Raise a small platform with crossed craft-stick pairs and a hand-driven input that changes their opening angle.
- Level
- Intermediate
- Time
- 75-110 min
- Cost
- $0-$10
Household engineering
Household Balance Scale
Compare unknown masses with a level beam, equal arm lengths, hanging cups, and simple calibration marks.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$5
Household engineering
Rolling Can Racer
Hide a twisted rubber-band weight inside a round container and use stored energy to roll the can forward.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$5
Household engineering
Rubber-Band Paddle Boat
Turn a twisted rubber band into paddle rotation and tune a lightweight tray boat for straight, repeatable travel.
- Level
- Beginner
- Time
- 40-65 min
- Cost
- $0-$6
Household engineering
Balloon Hovercraft
Release balloon air beneath a lightweight disk to create a thin cushion that reduces sliding friction.
- Level
- Beginner
- Time
- 30-50 min
- Cost
- $0-$5
Household engineering
Magnetic Maze
Guide a steel token through a covered maze using a safely enclosed magnet beneath the board.
- Level
- Beginner
- Time
- 35-60 min
- Cost
- $0-$8
Household engineering
Gravity Marble Timer
Create a repeatable rolling timer by tuning a marble path with slopes, gates, and energy-losing turns.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$8
Household engineering
Chain Reaction Machine
Link ramps, levers, rolling objects, and falling cups into a reliable multi-stage machine that completes one simple task.
- Level
- Intermediate
- Time
- 75-120 min
- Cost
- $0-$10
Household engineering
Egg-Drop Capsule
Protect a simulated fragile payload by increasing stopping time, controlling orientation, and testing from safe indoor heights.
- Level
- Intermediate
- Time
- 60-100 min
- Cost
- $0-$8
Household engineering
Indoor Parachute Drop Test
Compare parachute canopy area while lowering the same lightweight payload through a safe indoor drop.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$5
Household engineering
Paper Helicopter Flight Test
Fold paper rotors that autorotate during a safe indoor drop and test how blade length changes descent time.
- Level
- Beginner
- Time
- 30-50 min
- Cost
- $0-$2
Household engineering
Wind-Powered Sail Car
Capture airflow with an adjustable paper sail and tune a lightweight rolling chassis for speed and straight travel.
- Level
- Beginner
- Time
- 40-65 min
- Cost
- $0-$7
Household engineering
Water-Hydraulic Lift
Connect water-filled syringes to raise a guided platform and compare input travel, output travel, and force.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$12
Classroom challenges
Marble Run Challenge
Build a contained marble route with drops, turns, and a target finish while managing speed and reliability.
- Level
- Beginner
- Time
- 45-75 min
- Cost
- $0-$6
Classroom challenges
Longest Paper Cantilever
Extend paper beyond a desk edge while supporting a fixed tip load, then tune folds and counterbalance.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$2
Classroom challenges
Strongest Index-Card Beam
Turn identical index cards into beams and compare how cross-section geometry changes load capacity.
- Level
- Beginner
- Time
- 35-60 min
- Cost
- $0-$3
Classroom challenges
Slowest Marble Track
Design the slowest reliable marble descent using a fixed height, path length, and material budget.
- Level
- Intermediate
- Time
- 55-85 min
- Cost
- $0-$6
Classroom challenges
Cup-Stacking Mechanical Hand
Build a string-driven cardboard hand that grips paper cups and complete a timed stacking task.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$8
Classroom challenges
Load-Bearing Tower
Build the tallest paper-and-tape tower that supports a fixed top load and survives a gentle stability test.
- Level
- Intermediate
- Time
- 55-90 min
- Cost
- $0-$5
Classroom challenges
Bridge Under Budget
Design a bridge under a points budget, purchase materials strategically, and optimize load capacity per unit cost.
- Level
- Intermediate
- Time
- 70-110 min
- Cost
- $0-$6
Classroom challenges
Tabletop Zipline Carrier
Build a carrier that travels down a low tabletop line, delivers a payload, and stops inside a target zone.
- Level
- Beginner
- Time
- 40-65 min
- Cost
- $0-$6
Classroom challenges
Classroom Rescue Device
Design a remote tool that retrieves a model supply package from a taped hazard zone without crossing the boundary.
- Level
- Intermediate
- Time
- 65-100 min
- Cost
- $0-$8
Classroom challenges
Rube Goldberg Switch
Create a five-stage chain reaction whose final motion presses a low-voltage switch reliably.
- Level
- Intermediate
- Time
- 60-95 min
- Cost
- $0-$8
Classroom challenges
Mechanical Advantage Lift Challenge
Choose a lever, pulley, wheel-and-axle, or combination system to lift the same load with the smallest measured input force.
- Level
- Intermediate
- Time
- 60-95 min
- Cost
- $0-$10
Classroom challenges
Gear Ratio Race
Configure equal vehicles for speed or pulling force, predict their ratios, and compare performance in two fair races.
- Level
- Intermediate
- Time
- 55-85 min
- Cost
- $0-$15
Classroom challenges
Friction Investigation Sled
Pull the same weighted sled across different surfaces and measure the force needed to start and sustain motion.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$6
Classroom challenges
Center-of-Mass Balancing Sculpture
Arrange lightweight masses on a sculptural frame so the combined center of mass stays above a tiny support point.
- Level
- Beginner
- Time
- 40-65 min
- Cost
- $0-$6
Robotics/electronics
Low-Cost Robot Arm
Build a two-joint cardboard arm with two low-voltage servos, a simple claw, and constrained motion controls.
- Level
- Advanced
- Time
- 150-220 min
- Cost
- $0-$35
Robotics/electronics
Bristlebot
Offset a tiny motor mass to create vibration and tune angled bristles into directional motion.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$10
Robotics/electronics
Bumper-Switch Rover
Build a two-motor rover whose front bumpers trigger a timed reverse-and-turn escape behavior.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$30
Robotics/electronics
Line-Following Robot
Use two reflectance sensors and differential motor control to follow a high-contrast tabletop track.
- Level
- Advanced
- Time
- 140-220 min
- Cost
- $0-$45
Robotics/electronics
Light-Seeking Robot
Compare two light sensors and steer a differential-drive rover toward a diffuse flashlight target.
- Level
- Advanced
- Time
- 130-200 min
- Cost
- $0-$45
Robotics/electronics
Microcontroller Servo Pointer
Turn a knob to position a low-voltage servo pointer and calibrate command values against measured angles.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$18
Robotics/electronics
Traffic Light Controller
Program red, yellow, and green LEDs as a timed state machine with a pedestrian request button.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$12
Robotics/electronics
LED Reaction Timer
Measure response time to a randomly delayed LED cue while rejecting early button presses.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$15
Robotics/electronics
Conductivity Tester
Use a current-limited LED probe to compare whether common dry materials complete a low-voltage circuit.
- Level
- Beginner
- Time
- 35-55 min
- Cost
- $0-$8
Robotics/electronics
Tilt Alarm
Use a low-voltage tilt switch and transistor to sound a buzzer when a model container tips beyond a chosen angle.
- Level
- Beginner
- Time
- 40-60 min
- Cost
- $0-$10
Robotics/electronics
Ultrasonic Distance Meter
Send an ultrasonic pulse, time its echo, and display the measured distance to a flat target.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$18
Robotics/electronics
Automatic Night Light
Use a photoresistor voltage divider and transistor to turn on a low-voltage LED when the room becomes dark.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0-$10
Robotics/electronics
Mini Motorized Conveyor
Build a guarded low-voltage belt conveyor with tension adjustment, motor driver, and repeatable package test.
- Level
- Advanced
- Time
- 140-210 min
- Cost
- $0-$35
Robotics/electronics
Servo-Powered Claw
Drive a two-jaw linkage with a low-voltage servo and calibrate grip angles for soft classroom objects.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0-$24
Robotics/electronics
Drawbot
Build a two-motor differential robot that carries a marker and draws paths from timed wheel commands.
- Level
- Intermediate
- Time
- 75-115 min
- Cost
- $0-$25
Robotics/electronics
Scribblebot
Mount an enclosed vibration motor on a marker tripod and tune mass position to create repeatable drawing patterns.
- Level
- Beginner
- Time
- 40-65 min
- Cost
- $0-$12
Robotics/electronics
Capacitive-Touch Cardboard Piano
Turn foil-covered cardboard keys into capacitive touch inputs that play a simple five-note scale.
- Level
- Intermediate
- Time
- 75-120 min
- Cost
- $0-$20
Robotics/electronics
Hand-Crank Generator Demo
Turn a low-voltage DC motor by hand, measure generated voltage, and light an LED through rectification and current limiting.
- Level
- Intermediate
- Time
- 60-90 min
- Cost
- $0-$18
Robotics/electronics
Low-Voltage Electromagnet Lifter
Wind an insulated coil around an iron core, switch it safely with a transistor, and lift steel paper clips for short timed trials.
- Level
- Intermediate
- Time
- 70-110 min
- Cost
- $0-$15
Coding/game projects
Reaction-Time Game
Create an unpredictable on-screen cue, reject early presses, measure reaction time, and summarize five trials.
- Level
- Beginner
- Time
- 45-70 min
- Cost
- $0
Coding/game projects
Gear-Ratio Simulator
Build a browser simulator that calculates speed, torque, and direction for a simple two-gear pair and animates both rotations.
- Level
- Intermediate
- Time
- 75-120 min
- Cost
- $0
Coding/game projects
Virtual Robot Maze
Program a grid robot to navigate walls using turn-and-move commands, collision checks, and a reusable path queue.
- Level
- Intermediate
- Time
- 90-140 min
- Cost
- $0
Coding/game projects
MakeCode Physics Platformer
Create a tile-based platformer with gravity, jumping, coins, hazards, camera follow, and a complete win-and-restart loop.
- Level
- Advanced
- Time
- 120-180 min
- Cost
- $0