Logic Lab

Logic Lab is a free logic gates game. Students are locked in the Logic Lab after dark, and every light, door and alarm runs on logic gates that need wiring up. They drag gates onto the board and connect them with wires, from a single NOT gate that switches on a night light to a 2-bit adder that unlocks the way out. A live truth table shows, for every combination of inputs, what the circuit should do and what it actually does, and the Expression tab writes the circuit as Boolean algebra.

How to play

Each level has inputs on the left (switches, sensors, keys and buttons) and outputs on the right (lamps, doors, a bell, a siren and lights). Drag a gate from the bar at the bottom onto an empty slot, then drag from one pin to another to connect a wire. Wires carrying a 1 glow orange. Tap an input, or a row of the truth table, to try different inputs and watch the circuit respond. When every row has a tick, press Test it to run through the whole truth table.

Each level earns up to three stars: one for a circuit that works, two for using no more than a few extra gates, and three for using the fewest gates we know.

The levels

#	Level	Years	Big idea
1	Lights Out	9	NOT gates
2	Two Keys	9	AND gates
3	Ring the Bell	9	OR gates
4	Burglar Alarm	10	Combining gates: A AND (B OR C)
5	Landing Light	10–11	Exclusive OR from AND, OR and NOT
6	Majority Vote	11	Simplifying a Boolean expression
7	Only NAND	12	NAND as a universal gate
8	Half Adder	12	Adding two bits
9	The Calculator	13	A 2-bit adder

Tips for teachers

• Years 9–10: before students build each circuit, ask them to fill in the truth table on paper. The game’s table then checks their answer as well as their circuit.
• Years 10–11: after Burglar Alarm and Majority Vote, open the Expression tab and ask students to read the Boolean expression aloud, then write it in A · B + C notation.
• Years 12–13: Only NAND leads into De Morgan’s laws, and the last two levels build the half and full adders on the A-level Computer Science specifications.

Every level ends with a short “What you learned” summary you can use as a plenary.