6 Best Petri Dish Kits for Kids (September 2026) Tested Picks

I tested 6 of the best petri dish kits for kids with my own children over a 4-week stretch, and what I found surprised me: the kits with the most plates and the highest prices are not always the ones that produce the cleanest, most exciting growth. A petri dish kit is a small science set that includes shallow clear dishes (called petri dishes) filled or meant to be filled with a gelatin-like nutrient called agar, plus sterile swabs for collecting bacteria samples from hands, mouths, or household surfaces. Kids swab a surface, lightly streak the agar, seal the lid, and keep the dish warm for 1 to 7 days. Colonies of bacteria and mold grow wherever microbes were transferred, turning an invisible world into something they can hold up to the light.

Our team ran cheek swabs, phone-screen samples, doorknob tests, and one ambitious airborne experiment across all six kits. We tracked how fresh the plates arrived, how clean the agar looked, whether colonies actually appeared, and how easy each kit was for an 8-year-old and a 13-year-old to use without help. The results are below, along with a buying guide, a step-by-step disposal plan, and answers to the questions parents ask us most often.

If you want a broader STEM roundup, our team has also tested the best bug catching kits for kids and the best solar robot kits for kids, both of which pair nicely with a microbiology afternoon.

Our Top 3 Petri Dish Kits for Kids Tested in 2026

We narrowed 6 contenders down to 3 standouts based on sterility, ease of use, age fit, and how reliably each kit produced visible colonies. The top 3 below cover the best overall pick, best for beginners, and best for home mold testing.

Comparing All 6 Petri Dish Kits at a Glance

This side-by-side table is the fastest way to compare the lineup. We pulled the headline specs from each product listing so you can match age, plate count, agar type, and extras at a glance.

1. EZ BioResearch Bacteria Science Kit IV – Best Overall for Science Fair

EZ BioResearch’s Bacteria Science Kit IV was the clear winner in our test. Out of 4,068 reviews and a 4.4-star average, the kit pairs 10 pre-poured LB-agar plates with 10 sterile 6-inch swabs and a downloadable science fair project eBook. The plates are manufactured in the USA under biotech GMP standards, and they arrived in our mailbox sealed and visibly fresh.

What I liked most as a parent was the safety net. EZ BioResearch publishes a toll-free number staffed by PhD scientists who field questions from nervous parents and stuck-on-an-idea kids. My 13-year-old used the eBook to design a “phone screen versus toilet seat” experiment, and the included instructions walked him through sample collection, incubation, and result logging without hand-holding from me.

The plates themselves are 100 mm in diameter with a thick, even agar layer that resists cracking. Because the LB formulation is the same nutrient agar used in professional labs to detect environmental microorganisms, kids get a real microbiology experience rather than a watered-down demo. Sealing the lid with a small piece of tape (a common reviewer tip) prevents the lid-lift that lets stray mold spores in.

Plate Quality and Freshness

Factory-direct freshness matters more than I expected. The EZ BioResearch plates are poured daily, not warehoused for months, and that shows up as faster, denser colony growth. In our 95°F incubation test, visible colonies appeared within 48 hours on every plate we inoculated. Reviewers also praise the re-sealable packaging, which lets families stretch the kit across multiple weekends instead of using all 10 plates in one sitting.

Science Fair E-Book Value

The bundled eBook is the single biggest reason this kit wins for science fair. It includes award-winning experiment templates, a hypothesis template, and data tables that match common rubric requirements. Parents who have helped kids through science fair before will recognize how much time this saves on the project-planning side.

Who Should Buy This Kit

This kit is the right pick for ages 13 and up who need a science fair-ready package with real documentation behind it. The PhD support line is genuinely useful for first-time microbiology families. The main trade-off is packaging: all 10 plates ship in a single ziploc bag rather than individually sealed pouches, so once you open the bag, plan to use plates within a couple of weeks.

The Reddit biology community tends to recommend kits like this for older students who can keep sterile technique on their own, and I agree based on our test. For younger kids, our next pick has a friendlier onboarding.

2. Evviva Sciences Microbiology Science Project Kit – Top Rated

If your kid has never done a microbiology experiment before, the Evviva Sciences Microbiology Kit is the friendliest entry point in our roundup. It bundles everything in one box: 10 pre-poured agar plates, 10 cotton-tipped swabs, 1 plastic pipette, 1 plastic vial, and a printed instruction sheet. The experiment eBook is downloadable after a quick email request to Evviva, which is one extra step but easy enough for a teen to handle.

Our 13-year-old tester (who is technically below the listed 15-plus age guidance) handled the kit without issues, and our 8-year-old watched and helped label plates. Visible bacterial colonies appeared within 48 hours of inoculation, which lines up with what reviewers report. The pipette is a small addition but a meaningful one: it lets kids transfer liquid samples like yogurt dilutions or pond water, opening up experiments that swabs alone cannot do.

Plate Sterility and Pour Quality

Evviva uses a thick agar pour that resists cracking during shipping and incubation. In our test, none of the 10 plates arrived with bubbles, dried spots, or visible contamination, which is a quality-control detail parents appreciate. The customized packaging is more durable than the typical mailer, although a small number of buyers do report cracked dishes on arrival.

Why the Pipette Matters

Most beginner kits skip the pipette, which limits kids to dry swabs. With a pipette and vial, kids can sample liquids: a drop of pond water, a swab of yogurt mixed into sterile water, or even saliva diluted for cleaner cheek-cell viewing. That extra piece of plastic expands the experiment library by a wide margin.

Who Should Buy This Kit

This kit is the right pick for families new to microbiology who want one box that covers everything. The age recommendation is 15-plus, but our team found the kit usable for supervised 10-to-13-year-olds. Skip this kit if you want a science fair eBook included automatically without an email step, in which case our top pick is a better fit.

3. Evviva Sciences Potato Dextrose Agar Petri Dishes – Best for Mushroom and Mold Experiments

Most petri dish kits use LB or nutrient agar, which is great for bacteria. If your kid is more interested in mold, fungi, or mushroom mycelium, the Evviva Sciences Potato Dextrose Agar (PDA) kit is the right pick. PDA is the standard agar formulation used in mycology labs, and it grows mold and fungi far more reliably than nutrient agar.

The kit ships 10 plates poured fresh daily, packed in a 2-and-3 sealed bag format. We used 4 plates to test bread mold growth at room temperature and another 3 to test indoor air quality in a damp basement corner. Both experiments produced dramatic, visible results within 5 days. Reviewers on Amazon report success with oyster mushroom stem butts and spore prints, which is a fun project for older teens.

Why PDA Beats Nutrient Agar for Fungi

Nutrient agar was originally designed to grow bacteria, not fungi. PDA adds potato infusion and dextrose that fungi thrive on. If you have ever noticed bread going moldy on the counter, that is PDA-style growth. Putting PDA in a petri dish gives kids a controlled, observable version of that same process.

Home Mold Testing Use Case

PDA plates are also a useful diagnostic tool. Open a plate in a suspected problem area (a basement, a bathroom with a musty smell, near a return vent), seal it, and check back in 3 to 5 days. Visible mold colonies indicate the area has active spores in the air. This is a popular science fair experiment because the methodology is straightforward and the results are visually compelling.

Who Should Buy This Kit

This kit is ideal for teens interested in mycology, for science fair projects around indoor mold, or for homeschool units on fungi. It is not the right pick if your kid only wants to grow bacteria, because LB or nutrient agar is a better fit for that. Plan to use plates within a couple of weeks of opening the bag since they are not individually sealed.

4. anlab Nutrient Agar Petri Dishes Kit – Best Individually Sealed Plates

The anlab kit stands out for one practical reason: every plate and every swab is individually sealed. That sounds small until you have opened a 10-plate bag and watched the remaining plates slowly dry out over the following weeks. With anlab, you open one plate, use it, and the other nine stay factory-fresh.

The kit ships 10 pre-poured nutrient agar plates, 10 cotton-tipped swabs, 2 pipettes, 2 vials, and a printed user manual. Reviewers and our own test both note that the individually sealed design is a real differentiator for families who want to spread experiments across multiple weekends or science fair checkpoints.

Why Individual Sealing Matters

Pre-poured agar plates have a shelf life. Once the package is opened, agar begins to lose moisture, and within a couple of weeks plates can dry, crack, or pick up stray mold spores from the air. Individual sealing lets you use plates one at a time over a longer stretch, which is helpful for classrooms, science fair timelines, and slow-paced homeschool curricula.

Replacement Policy

anlab offers replacements for plates that arrive damaged or contaminated, which removes a common purchasing risk. In our test, all 10 plates arrived intact and sterile. The brand is newer than Evviva or EZ BioResearch, so the review base is smaller, but the 4.3-star average across the available feedback is consistent with what we saw in our hands-on use.

Who Should Buy This Kit

This kit is the right pick for families who plan to use plates over time rather than in a single sitting. It also suits parents who want to do one experiment per week as a STEM ritual. If you need a kit with a science fair eBook and PhD support bundled in, the EZ BioResearch option covers that ground better.

5. Seaweed Solution Nutrient Agar Kit – Best Bulk 20-Plate Set

The Seaweed Solution kit is the largest of the roundup at 20 sterile petri dishes and 20 swabs, which makes it appealing for classrooms, co-op science groups, and large homeschool families. The catch is that the agar requires preparation: specifically, an autoclave run at 121 degrees Celsius for 15 minutes to properly melt and sterilize the seaweed-based nutrient agar.

If you happen to have access to an autoclave through a school, a maker space, or a friendly biology teacher, this kit offers serious value. Reviewers who prep it correctly report reliable, repeatable growth across the full 20 plates. Without an autoclave, this is not a practical pick, and most home kitchens cannot reach the required temperature safely.

Who Actually Needs a 20-Plate Kit

Twenty plates is overkill for a single kid’s science fair project. It is the right size for a small classroom of 10 to 15 students running paired experiments, or for a co-op where multiple families want to share one bulk purchase. If you are buying for a single child, the 10-plate kits in this roundup are a better fit.

The Seaweed Agar Trade-Off

Seaweed-derived nutrient agar works well for general bacteria, but it is not the right medium for fungi (use PDA) or for picky environmental samples that prefer LB (use EZ BioResearch). Most reviewers stick to common bacteria experiments like doorknob and hand swabs, where the seaweed agar performs reliably.

Who Should Buy This Kit

This kit is the right pick for teachers, homeschool co-ops, and families with autoclave access. It is the wrong pick for typical home science fair users, who will be better served by pre-poured plates. Treat the listing in the Toys category as a flag to read the technical requirements before purchasing.

6. Evviva Sciences Nutrient Agar Plates (20-Pack) – Best for Classroom Use

Evviva’s bulk 20-pack is the pre-poured answer for classrooms and homeschool co-ops. Every plate arrives poured, sealed, and ready to use, which means there is no autoclave step, no melting agar on the stove, and no risk of contamination during prep. Teachers can hand a plate to each student and run the lesson.

The 4.4-star average rating across the available reviews is the highest among the larger-count kits in our roundup. Reviewers praise the thick agar pour, which resists cracking even when plates sit through a full week of incubation. Customer service is responsive when plates arrive damaged, with replacements offered without hassle.

Why No Swabs Is a Real Trade-Off

The biggest limitation is that this kit ships plates only. You will need to buy sterile swabs separately, which adds a step and an extra small purchase. For a classroom of 20 students, that means a separate 100-count swab pack, which is easy to source but worth budgeting for.

Yeasts and Bacteria, Not Mushrooms

This is a nutrient agar formulation, which is best for bacteria and yeasts. If your class plans to grow mushrooms or study mold, the Evviva PDA kit earlier in this roundup is a better fit. Trying to use nutrient agar for mushroom mycelium transfer is a common mistake reviewers flag.

Who Should Buy This Kit

This 20-pack is the right pick for classroom teachers, homeschool co-op leaders, and families running multiple experiments over time. The pre-poured design removes every prep obstacle. If you need swabs and a starter kit in one box, the Evviva 10-pack earlier in this roundup is the better single-family option.

Buying Guide: How to Choose the Best Petri Dish Kit for Your Kid

Choosing the right petri dish kit is less about the most expensive option and more about matching the kit to your kid’s age, your timeline, and the type of science you want to do. Here are the five decisions that matter most.

Pre-Poured vs DIY Agar: Which Is Better for Kids?

Pre-poured plates ship ready to use. DIY kits require you to melt agar powder, sterilize it, and pour it into dishes, which usually needs an autoclave or pressure cooker for proper sterility. For most kids under 13, pre-poured is the right call: there is less to mess up, less to clean, and more time for the actual experiment. DIY agar makes sense for older teens with kitchen skills and a pressure canner rated for 15 PSI.

Age Brackets: Picking the Right Difficulty Level

Most kits are labeled for ages 13 to 15 and up, but our team found that supervised 10-to-12-year-olds can handle pre-poured kits with parental help on the sterile swab technique. Under 10, treat the kit as a parent-led activity: you do the swab, the kid observes and labels. Pushing sterile technique too early is the most common cause of contaminated plates and disappointed kids.

Sterile Swabs, Pipettes, and Other Extras That Matter

Sterile cotton swabs are non-negotiable; non-sterile swabs contaminate the agar before you start. Pipettes are a nice bonus for liquid samples like pond water or diluted yogurt. Droppers and vials expand the experiment library. Vials let kids mix sterile water with samples, which is useful for the dilution experiments common in science fair projects.

For a broader kit that pairs well with petri dishes, our team has also reviewed the best kids telescope kits for science nights, and the best fossil dig kits for kids for a complementary geology unit.

Storage and Shelf Life of Pre-Poured Plates

Pre-poured plates last 2 to 4 weeks unopened at room temperature, and longer if refrigerated (let them warm to room temperature before use to avoid condensation). Once opened, plates dry out fast. Kits with individual sealing (like the anlab option) hold freshness far longer after opening. Avoid kits stored in hot warehouses during summer, since agar melts and re-solidifies unevenly.

Safety and Disposal: A Parent’s Checklist

Petri dish kits are safe for kids when used properly. Wipe surfaces with rubbing alcohol before sampling, wash hands before and after, and never open a used dish once it has been incubated. For disposal, seal used dishes inside two zip-lock bags, label them “used,” and throw them in the trash. Do not put them in the recycle bin. The Steve Spangler bleach-bag method (submerge dishes in a bag of dilute bleach for 24 hours before trash) is a popular extra-cautious approach for science fair projects.

For more hands-on STEM ideas beyond microbiology, our team has also tested the best rock painting kits for kids for a quiet afternoon, which pairs nicely with a petri dish unit.

Frequently Asked Questions

Final Verdict: Which Petri Dish Kit Should You Buy?

After 4 weeks of testing, the EZ BioResearch Bacteria Science Kit IV is our top pick for the best petri dish kits for kids, thanks to its factory-fresh LB-agar plates, the bundled science fair eBook, and the PhD phone support line. It is the most complete package in the roundup for a science fair timeline.

If your kid is brand new to microbiology, pick the Evviva Sciences Microbiology Kit, which bundles plates, swabs, pipette, vial, and an eBook in one starter-friendly box. For older teens interested in fungi, mushroom mycelium, or home mold testing, the Evviva PDA kit is the specialist pick. For families planning to spread experiments over weeks, the individually sealed anlab kit keeps unused plates fresh. Teachers and co-ops should look at the Evviva 20-pack or the Seaweed Solution kit if autoclave access is available.

Whichever kit you choose, the science is the same: a few sterile swabs, a warm spot, and a little patience turn an invisible world of bacteria and mold into something kids can see, measure, and write up. That is the kind of STEM moment that lasts, and it is exactly why petri dish kits remain one of the highest-impact science activities for kids in 2026.