My 11yo son's latest obsession is creating miniature “ecosystems” in glass jars using sediment, plants, and water from wherever our RV happens to be parked. I thought he might enjoy having some supplies on hand that are a bit more curated so he wouldn't have to hunt down the perfect moss or whatever, and my searches brought me to this terrarium starter kit from Cute Farms.

The kit comes in three sizes, each of which comes with enough potting soil (blended with activated charcoal), gardening vermiculite, and preserved moss to get terrariums going in a number of containers:

1. Small ($19) — Enough for 6–8 small eight-ounce glass terrariums, 2–4 pint-sized mason jars, or 2–3 large terrariums.
2. Medium ($23) — Enough for 10 small eight-ounce glass terrariums, 5 pint-sized mason jars, or 1–2 large terrariums.
3. Large ($26) — Enough for 12 small eight-ounce glass terrariums, 7 pint-sized mason jars, or 2–3 large terrariums.

(In the case of the medium and large kits, you also get a collection of pea pebbles and river stones for use as either a base layer and/or decorative accents.)

The kits also include a 1-fluid-ounce spray bottle of plant food, a set of bamboo tongs, a bamboo stick, a natural-hair brush, and a few mini dinosaurs to place as desired. You'll have to provide your own small plants/succulents and glass containers, but otherwise I think these are quite well-made kits that any science-loving kid will adore.

Check out and purchase the kits here.