With a microscope, you can watch a crystal garden grow right on a glass slide.
You can do this by dissolving two tablespoon of salt in one-quarter cup of water. You will notice that some of the salt will remain in the bottom of the cup.
Next, place a drop of the clear liquid on a slide and let it spread a little. Put the slide aside, without the cover slip, for a few minutes. Or you could also move it back and forth under a warm light bulb until the solution begins to dry. Now, insert it under the microscope and focus on the outer portions of the drop. Soon, square crystals of different sizes will form, rimmed by dark parallel lines. Salt crystals grow faster at the edges than at the center, building up steps that look like nests of open glass boxes. Move the mirror so that no light is transmitted from below, and you will see the crystals change to gleaming three-dimensional shapes on a dark background. For crystals with different shapes, try the same experiment with your microscope by using basic acid instead of salt.
You could also find crystals of glittering quartz and other minerals by using the sand as your sample for microscopy. Under the microscope, the shape of sand grains can tell something about their history. The rounder and blunter they are, the longer they are likely to have tumbled in water or wind, rubbing their edges against one another. You might also be surprise to find a rich sprinkling of shell fragment among the sand grains. For your information, there are rare beaches which have stuff that look like a white sand but if you examine them under the microscope they will reveal themselves as a myriad of tiny shell pieces of delicate shapes and colors.