Flash questions
Short drills on core skills, drawn at random each time you open one. A wall of cards to project, print or run as a timed slideshow — answers stay hidden until you ask for them.
Computer scienceHigh school
Binary and hexadecimal conversions
Converting a byte between base 2, base 10 and base 16, the way the machine does.
Open the wall
Computer scienceHigh school
Powers of two
From 2¹ to 2¹⁶: the sizes that turn up everywhere in computing, both ways round.
Open the wall
What are flash questions for?
A flash question is answered in seconds, in your head. Strung into a short series, they keep sharp the basics — times tables, fractions, conversions, formulas — that longer exercises already assume. Every wall is drawn afresh: the same series never comes back identical, unless you keep its address.