One challenge is that, in test tube experiments, "it's always difficult to know if you're missing something," he said. Related: The 12 deadliest viruses on Earth ...

Science’s Test Tube Chemistry Lab is a solid choice. For starters, there are over 50 experiments to learn, including a test tube lava lamp, and STEM projects involving the metals copper and zinc.

One glass test tube can cost between $1 and $5. Bubble wrap, by contrast, is dirt cheap. One square foot of it, with about 100 to 500 bubbles depending on bubble dimensions, costs only 6 cents ...