Cube and net questions are some of the most feared on Non-Verbal Reasoning papers — but they are actually some of the most learnable. Once your child understands the small handful of rules that govern how a flat net folds into a solid cube, these questions turn from guesswork into a quick, confident tick. In this guide we walk through the opposite-face rule, the eleven valid cube nets, the classic traps that catch children out, and a timing plan so your child never loses easy marks by rushing. Everything here maps onto the 3D spatial questions that GL Assessment builds into its NVR papers.
Where cube nets sit in the 11+
Since CEM withdrew its separate 11+ tests around 2022–2023, GL Assessment has become the dominant provider across most selective regions, with CSSE running the Essex consortium and ISEB serving many independent seniors. GL NVR papers are multiple-choice, answered on a separate OMR sheet, and tightly timed at roughly 35–50 seconds a question. Cube and net items belong to the 3D or spatial family of NVR, alongside rotations, reflections and shapes-from-above. They test whether a child can mentally fold, unfold and rotate a solid — a skill that responds very well to short, regular practice on our free worksheets and timed mock papers.
The opposite-face rule
This single rule solves most cube-net questions. On a flat net, any two faces with exactly one square between them in a straight line end up opposite each other when the net folds. Faces that share an edge fold up to become adjacent. That gives you a fast check: opposite faces can never touch on the finished cube, so if a question shows two symbols that should be opposite sitting next to each other on the cube, that option is wrong.
A worked example on the common cross-shaped net: label the four squares in the horizontal arm 1–2–3–4 from left to right, with square 5 above square 2 and square 6 below square 2. Fold it in your head and you find three opposite pairs — 1 and 3, 2 and 4, and 5 and 6. Notice each pair has one square gap between them. Teach your child to draw these pairs before they even look at the answer options.
The eleven valid cube nets
There are exactly eleven different nets that fold into a cube. Knowing they exist stops children panicking when a net looks unusual. They fall into four broad groups:
| Net family | Description | How many |
|---|---|---|
| 1-4-1 | A row of four squares with one square above and one below the row | Six |
| 2-3-1 | A row of three with staggered squares above and below | Three |
| 2-2-2 | A staircase of three offset pairs | One |
| 3-3 | Two rows of three offset by one square | One |
The friendly headline: six squares joined edge-to-edge, with no overlaps and the right arrangement, will fold into a cube. The cross (a 1-4-1 net) is simply the most familiar of the eleven. Our revision hub has a printable eleven-nets reference your child can keep by their desk.
Spotting the impostor net
Many questions ask which shape is not a valid cube net. Run this quick checklist before choosing:
- Count the squares. More or fewer than six can never be a cube net.
- Check the connections. Every square must join another along a full edge, not just touch at a corner.
- Mentally fold for overlaps. If two faces would land on the same spot, the net fails.
- Watch for four-in-a-square. Any 2×2 block of four squares cannot fold — two faces always overlap.
Faces with symbols: the extra layer
Harder GL items print an arrow, dot or shape on each face and ask which folded cube matches. Here the visual attributes matter: your child must track orientation (which way an arrow points), position (corner or centre), and which faces sit opposite. The pro move is to fix on one distinctive face, decide what must be opposite it, then eliminate any cube showing that symbol in the wrong place. Elimination is faster and safer than trying to fold the whole cube perfectly.
Timing and the Standardised Age Score
GL marks are converted into a Standardised Age Score (SAS), adjusted for your child's exact age in months so younger pupils are not disadvantaged. The range runs roughly 69–141, with 100 the average and many grammar schools looking for about 111 or above, though exact marks vary by area and year. Because harder 3D items carry the same weight as easy ones, getting them right lifts the SAS noticeably. Use a simple pacing plan:
| Stage | Approach |
|---|---|
| First pass | Answer every net you can inside 40 seconds each |
| Skip-and-return | Flag any symbol-cube taking longer; move on |
| Final sweep | Return to flagged items with time left, then guess unanswered |
Practise this rhythm on our GL-style papers and full mocks so it becomes automatic. For the wider spatial toolkit, our post on rotation, reflection and symmetry pairs perfectly with this one, and the exam guides cover the full NVR picture.
Common traps to avoid
- Assuming adjacent squares on the net stay adjacent visually — folding changes what your eye expects.
- Confusing a rotated correct answer with a wrong one; a cube can be turned yet still be right.
- Forgetting to check the opposite-face pairs before committing.
- Reading a symbol's direction as it lies flat, not as it points once folded upward.
Frequently asked questions
How many cube nets are there?
Exactly eleven distinct nets fold into a cube. The cross shape is the most common in practice papers, but all eleven can appear.
What is the fastest way to check a net?
Use the opposite-face rule: faces with one square between them in a straight line become opposite, and opposite faces can never touch on the finished cube.
How long should a cube-net question take?
Aim for about 35–50 seconds, matching the GL paper pace of roughly a question a minute. Flag and return to any that run long.