On Reflection...

Some clever, "secret" coding can be done using a small mirror and the REFLECTION SYMMETRY characteristic of many capital letters and some numbers.
Draw a good-sized version of the letter A on a piece of paper, place the edge of the mirror across the vertical center of the letter and you see that the reflected image in the mirror balances and exactly completes the letter. Similarly a mirror positioned through the center of the letter M completes that letter. This method works for other letters, such as B and E, when the mirror is placed horizontally. The letters O and X are completed by the reflection from a mirror held either vertically or horizontally.
In the entire alphabet the letters A, B, C, D, E, H, I, M, O, T, U, V, W, X and Y have this symmetry characteristic, as do the numbers 0 and 8.
Now delete the mirror "half" of each letter to form a "coded" version which the reader can only decipher using a mirror (or a fairly visual imagination). Here are the usable "code" signs in alphabetical order:
Broken Letters.
Here are some examples to start the ball rolling.
Half-shaded letters
And now some "encoded" examples.
Secret Messages
Slip complete letters or other asymmetrical letters into a puzzle now and then to adjust examples to various ability levels.
When you are tired of interpreting codes and spelling and reflecting it's nice to lighten up and relax by creating your own symmetrical project. Fold some paper up into many folds, grab the scissors and make a string of paper dolls, or animals, or snowflakes, or ... whatever.