I recently got a National Geographic Crystal Garden Kit courtesy of Incredible Novelties. Even though the age recommendation is for kids 8 years old or older, we decided to try it out as a family. So dad, mom and 3 year old, we all sat together to have fun with it.
The kit comes with 2 different tree patterns, markers to paint them, the liquid to grow the crystals, 2 bases for the trees, a geode sample, a booklet regarding crystals and the instructions on how to use the kit. To use it, you need to take the trees, paint them however you want, give them some shape by folding branches, put the 2 parts of each tree together and stand them on the bases. We all took different parts of the tree and started painting. My son had a lot of fun painting everything in orange, while my husband did a very minimalist look and I went as heavy as I could on color.
After you put it together, the instructions say to set them wherever you are going to leave them when they are growing and later. The point of this is because you cannot move the trees after or the crystals will fall, so be very careful and set them in their "final" place before using the special liquid!. We set them on a glass shelf and very carefully used the liquid. Then you have to wait. After an hour or so we started seeing some crystals growing already, and after 6 hours they were completely grown. We enjoyed doing this in the morning so we could see them change during the day :)
The crystals are very soft, so don't touch them unless necessary, although my son kept trying as much as he could :D After that, there is nothing much to do but admiring them. The instructions say to throw them in the trash after that but we left them there as much as we could, and after about 5 days the crystals just started falling apart. Pretty easy to clean though, so at that point we put them in the trash and we kept the geode and the booklet as a nice reminder.
The kit is $16.99 and can be found in Mastermind, Indigo, Staples, Walmart, Toys R US, and Independent Stores. It was really fun as a family activity and I'm sure older kids would get more fun out of the scientific aspect of it! I would definitely recommend it, specially for any kids that are interested on science.