Test tubes are handy for lots of projects and lessons.

• Classroom demos and simple experiments: Mixing small amounts, observing reactions, or comparing samples.
• Sample organization: Holding small quantities so they’re easy to label and compare.
• Crafts and storage: Storing beads, glitter, sand, or other small dry items.
• Displays and favors: Clear tubes can showcase colorful layers or themed decorations.

Tip: If you plan to heat contents, consider heat‑resistant glass. For spinning samples, look for items labeled for centrifuge or microcentrifuge use. Product descriptions can help you match the tube to your task.

You’ll see test tubes described by different names depending on use and size.

• Culture tubes: General purpose tubes, often used for classroom experiments.
• Centrifuge tubes: Sized and shaped for spinning in a centrifuge.
• Microcentrifuge tubes: Small 1.5–2 mL tubes for tiny samples.
• Reaction or sample tubes: Broad terms for mixing or holding samples.
• Demonstration tubes: Oversized tubes meant for visual display or teaching.

Names also reflect closures (corks, screw caps, snap caps) and materials (glass or plastic). Check capacity and dimensions in the listing to be sure it fits your project and rack.

Start with what you need to hold and how you’ll use it.

1. Match volume to task: Small (about 3–6 mL) for drops and dyes; mid (around 10–15 mL) for most classroom mixes; larger (up to ~30 mL) for displays or bulk storage.
2. Read dimensions: Listings often show diameter × length (e.g., 12 × 75 mm). Make sure they fit your rack or holder.
3. Consider closures: Corks are great for dry contents; screw or snap caps can help when transporting.
4. Factor in material: Glass tends to handle heat better; plastic is lightweight and easy to handle.

Photos and specs on the page can help you visualize scale before you buy.

There are several, but two common ways to group them are:

• By material: Glass tubes typically handle direct heat better and are popular for demonstrations. Plastic tubes (like polystyrene or polypropylene) are lightweight and convenient for handling, storage, and many classroom or hobby uses.
• By shape/closure: Round‑bottom tubes are common for mixing; flat or round‑base styles can stand upright. Closures vary—corks, snap caps, or screw caps—so pick what fits your project.

Check each item’s description for intended use and care notes. Using filters for material, capacity, and closure can help narrow your search.

Care depends on material, but a few basics can help extend usability.

• Rinse soon after use, then wash with mild dish soap and a soft brush.
• For plastic, avoid very hot water or abrasives that may scratch or cloud the surface.
• For glass, let hot tubes cool before washing to reduce thermal stress.
• Air‑dry inverted or in a rack; store upright in a holder or bin.
• Leave caps slightly open while drying to prevent trapped moisture.
• For classroom or craft setups, keep small caps and corks out of reach of young children when not in use.

Always follow any care notes provided in the product listing.