Materials: Glass container - I like to search the local thrift stores for weird jars, but you can find some inexpensive jars with lids at Target or any other local department store.
Gravel- you can get gravel at the hardware store or just pull some off your driveway, but remember to wash it before you use it.
Charcoal- You can get this at the grocery store or hardware store.
Sand or Soil- depending on the plant life you choose, you will need sand or soil. Sand for desert plants, and soil for succulents. All can be purchased at home& garden stores.
Plants- pick plants that will work well in this environment (mini cacti, jade plants, ivy, small palms, mini begonia, moss, and ferns)
Optional- rocks or other little statues or Dode-dads.
Step 1) wash glass container you plan to use
Step 2) add one layer of gravel, then a layer of charcoal, now a a-2 inch layer of sand or soil.
Step 3) Now it is time to add your plants. A good tool is a pair of chopsticks to help you poke plants into soil. Remember to use thick rubber or leather gloves for handling cacti.
Step 4) Add any little nik-naks or rocks at this time. I added a cute little plastic deer to live in mine :)
Now your terrarium is finished. Remember to place terrarium in a place that has suitable light for your plants. Also keep in mind some plants do not like terrarium lids (like cacti) .
Watering your terrarium: A good watering once every 2 weeks is enough. Soil should dry out between watering's for dry climate plants. Succulents require the least amount of watering. Usually the lid will keep in moisture making the terrariums a self contained eco-system.
Have fun and happy planting!