Optical illusions like this aren’t just about finding the right answer. They’re about the thrill of the challenge, the satisfaction of “getting it right,” and the fun of sharing your answer with ...

There are 10 fingers on these hands, 10 counters in the ten frame, 10 beads on the string, 10 dots on the ... Let's count in 10s. You can count in 10s using a number line. This number line starts ...