Inside or outside the loop
A twisty closed loop, or a fence round a field, with a star or a sheep somewhere in it. The student decides whether it is inside or outside, or taps every lettered point or sheep that is inside. The loop is drawn with no shading, so it is hard to tell at a glance.
The trick is to draw a straight line from the point to the edge of the picture and count how many times it crosses the loop. Each crossing goes from inside to outside or back, and the edge is outside, so an odd count means inside and an even count means outside. The working draws the line and numbers the crossings.
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What changes each time
- A new loop every time, never crossing itself
- A star, or sheep inside a fence
- One point, or three or four lettered ones
More shapes and angles practice
- Sides and corners of 2D shapes (Grade 2)
- Faces, edges and vertices (Grade 3)
- Sorting quadrilaterals (Grade 3)
- Turning and flipping letters (Grade 3)
- Counting squares of every size (Grade 3)
- Which piece fills the gap? (Grade 3)
- Symmetry on a grid (Grade 4)
- Rotations and reflections (Grade 4)
- Reading a protractor (Grade 4)
- Parallel and perpendicular lines (Grade 4)
- Parts of a circle (Grade 4)
- Draw without lifting your pencil (Grade 4)
- Can these sticks make a triangle? (Grade 4)
- 3D shapes: side view (Grade 5)
- Rectangle in a quarter circle (Grade 5)
- Painted cube puzzle (Grade 5)
- Rope around the Earth (Grade 5)
- Can dominoes cover the board? (Grade 5)
- Angles in a circle (Grade 6)
- Inscribed circle in a right triangle (Grade 8)