Zebra’s field with nobody to play against. The board arrives all black; tap a hexagon and it turns white. Hexagons of one colour that touch make a herd, and a colour is worth its herd sizes multiplied together. The two colours have to come out worth the same, which is easy, and then as large as the shape will allow, which is not.
The rules
A zebra's pelt is striped black and white. This one starts all black. Tap a hexagon to turn it white.Black scores by multiplying together the sizes of all its groups. White does the same.Make the two scores equal, and as big as you can.In the last pack, the two scores must be one apart instead.
What it gives you to practise
The same multiplication insight as Zebra with the opponent taken away, so there is nothing to react to and nowhere to hide: every board is a question about how one fixed shape can be cut. Chains, loops, diamonds and triangles each break differently. The last pack changes the rule — the two colours must miss each other by exactly one, three and three against four and two — and every target printed on a board is the true best, found by a computer trying every way of painting it.
In a classroom
The maximum is never printed on the board before somebody reaches it, and that is deliberate. A class can hunt for a number nobody has told them, and the board will say when they have it.
Share or embed
The whole puzzle at one address, with every board in it. Whoever opens it stays inside it, and their progress stays in their own browser.