📓 Fourth-grade Maths

Tap the card holding the answer. In Big numbers you type the digits into the nine-cell place-value table, one class at a time, then press the tick. In Angles you drag the protractor until its centre sits on the vertex and its base lies along the arm, then read the scale that starts at zero. A miss never turns red: the card wobbles and the working opens up, cutting quarters into eighths before adding, shifting the second partial product one column left, or estimating 57 : 21 by covering a digit. Five right in a row earns a star.