A quick note on expectations before the instructions, because "brain training" is a phrase that promises more than it can deliver. What these exercises reliably do is make you better at these exercises. Practising a sequence-recall task improves your sequence recall; practising timed arithmetic improves your timed arithmetic. Whether that improvement carries over into unrelated parts of life is a much weaker and much more contested claim, and we are not going to make it. Play these because the puzzles are enjoyable and because getting measurably better at a specific task is satisfying — not because a page told you it would raise your intelligence.
With that said, the three games here do load genuinely different mental machinery, and it is worth knowing which is which.
Cards lie face down in pairs. Flip two: if they match they stay up, if not they turn back over. Clear the grid in as few moves as possible. Three sizes are available — 4×4, 4×6 and 6×6 — and the game tracks moves, time, and your best result per size.
What this exercises is spatial working memory: holding "that symbol was in the second row, third column" available while you do something else. Two habits help concretely. First, when you flip a card you have seen before, resist flipping randomly for its partner and instead recall where the partner was; guessing costs you the move and teaches you nothing. Second, describe positions to yourself in grid terms rather than as a vague sense of "over there" — a deliberate label is far more durable than a visual impression. On the 6×6 board, most people find they can track roughly the last handful of cards seen, and the game becomes a question of managing that limit rather than exceeding it.
Nine tiles light up one at a time in a growing order; you repeat it back by clicking. Each successful round appends one more step, so level 8 means an eight-item sequence. One mistake ends the run and the sequence resets.
This is a serial recall task, and it has a well-known ceiling: raw sequences of arbitrary items get very hard somewhere in the single digits. The way past that ceiling is chunking — grouping the sequence into units so that eight items become three chunks. Recall "top-left, centre, bottom-right" as one movement shape rather than three separate positions. Many people also find that watching the path the highlights trace, rather than the individual tiles, extends their range noticeably. Neither trick increases your memory capacity; both reduce how much capacity the task demands, which is the only lever available.
Sixty seconds, multiple-choice arithmetic: addition and subtraction with two-digit numbers, and multiplication within roughly the times tables. You pick from four answers, so speed matters more than working the problem out longhand.
The efficient strategy is elimination rather than calculation. Check the last digit — 34 + 27 must end in 1, which usually kills two of the four options immediately. Estimate magnitude: 8 × 12 is near 100, so a choice in the sixties is gone without further thought. Only compute properly when two survivors remain. This is genuinely a different skill from careful arithmetic, and it is the one the format rewards.
If you would rather spend the time on games with more depth to them, our strategy guides cover solitaire, chess and sudoku in detail.