Reflective symmetry worksheet for students to practice reflecting shapes across dotted lines.

To solve this problem, we need to complete the reflective symmetry for each shape. This means drawing the "mirror image" of the shape on the right side of the dotted line.

How to do it:
1. Look at a point (dot) on the left shape.
2. Count how many squares it is away from the dotted vertical line.
3. Go to the right side of the dotted line and count the same number of squares outwards. Mark that new dot.
4. Connect the new dots in the same order as the original shape.

Here are the descriptions of the lines you need to draw for each numbered box:

* Box 2: The top-left corner is 3 squares left of the line; draw a point 3 squares right. The bottom-left corner is 2 squares left; draw a point 2 squares right. Connect them to mirror the zig-zag pattern.
* Box 3: The top spike points to a dot 1 square left of the line; draw a matching spike pointing to a dot 1 square right. The bottom part mirrors similarly.
* Box 4: The top horizontal line goes from the edge (4 squares left) to 1 square left of the line. Draw a matching line on the right from 1 square right to the edge (4 squares right). Mirror the zig-zags below it.
* Box 5: The top triangle tip is 1 square left of the line. Draw the tip 1 square right. The bottom "V" shape opens towards the line; mirror it so it also opens towards the line from the right side.
* Box 6: The diagonal line starts at the top-left corner (4 squares left). Draw a line starting at the top-right corner (4 squares right) going down to meet the center. Mirror the steps at the bottom.
* Box 7: The "M" shape has two peaks. The left peak is 2 squares from the line. Draw a right peak 2 squares from the line. Ensure the heights match exactly.
* Box 8: This is a quadrilateral. Map each of the 4 corners across the line. For example, the bottom-left corner is 3 squares left; place the new corner 3 squares right.
* Box 9: The shape touches the dotted line at two points. These points stay in the same place. Reflect the outer vertices (the ones furthest to the left) to the right side.
* Box 10: This is a complex zig-zag. Trace each vertex carefully. The top-most point is 1 square left of the line; draw its partner 1 square right. Continue down the chain.
* Box 11: Similar to Box 2 but taller. Mirror the long diagonal and the small steps.
* Box 12: A tall "N" or lightning bolt shape. The top-left corner is 3 squares left; draw the top-right corner 3 squares right.
* Box 13: A series of horizontal zig-zags. Each horizontal segment on the left must have an equal-length partner on the right.
* Box 14: An arrowhead pointing left. The tip is 1 square from the line. Draw a matching arrowhead pointing right, with its tip 1 square from the line on the right side.
* Box 15: A pentagon-like shape with an internal line. Reflect the outer boundary first, then reflect the internal "V" shape inside it.

Final Answer:
The solution involves drawing the mirror image of each shape across the vertical dotted line. For every point on the left shape, measure its distance from the center line and plot a corresponding point at the same distance on the right side, then connect these points to form the symmetrical half.