Easy math crossword
An easy math crossword is the short one: plus and minus only, small numbers, and a board you finish by always filling the equation that has one empty cell.
Easy uses addition and subtraction only. Every number is from 1 to 30. The grid is at most 9 by 9 and holds seven or eight equations. About half of the numbers are printed. The rest are blanks, and the bank starts with one tile for each blank.
Each equation is the short kind: one number, an operator, another number, and a result. There is no multiplication, no division, and no line with two operators. A usual board has a scoring target of about 37 seconds, five seconds for each blank.
Find an equation with a single empty cell and solve it. Filling it leaves another, so the chain does not stall and you never list candidates or guess. Where two equations cross they share that cell, which is what moves the chain.
A cell holds one positive whole number, never zero and never negative. Each tile is used once, the blank answers are all different, and there is one solution. Easy is a first game or a one-minute warm-up. Medium adds multiplication, and the first moment where no equation has a single blank left.