Last year, my nephew’s sixth birthday party turned into a chaos of inflatable bounce houses, sugar, and thirty kids who ran out of things to do in under an hour. I had been tasked with the “outdoor activities” and I was grasping at straws. That was the day I started researching ninja obstacle kits for kids, and I have not stopped since.
After testing eight different backyard ninja warrior kits over the past four months – yes, my lawn looks like a training facility right now – I have learned more about slackline tension, cargo net stitching, and ratchet mechanisms than I ever wanted to know. Parents planning a birthday party need the same confidence I now have after fifty-plus kids have crashed through my backyard course.
This guide covers the best ninja obstacle kits for backyard birthday parties in 2026, from full 60-foot slackline setups your kids can race through to tree-mounted climbing holds that turn any backyard into a ninja warrior playground. Every product on this list was tested with real kids at real parties, and I have included the rough numbers, the actual issues, and the exact setups that worked for groups of eight to twenty children.
Table of Contents
Top 3 Picks for Backyard Birthday Parties
Trailblaze Ninja Warrior Obstacle Course
- 2x55ft double slackline
- 10 obstacles
- 450lb capacity
- carry bag
Gentle Booms Sports 56ft Ninja Kit
- 8 obstacles
- quick-install buckles
- CPC compliant
- stainless steel
Best Ninja Obstacle Kits for Backyard Birthday Parties in 2026
| Product | Specifications | Action |
|---|---|---|
| Trailblaze Ninja Warrior Obstacle Course |
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 Trelines 36ft Ninja Adventure Kit |
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 Hapfan 50ft Ninja Warrior Course |
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| Gentle Booms Sports 56ft Ninja Kit |
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 Dripex 60ft Ninja Obstacle Course |
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 Slackers Deluxe Ninjaline 56ft |
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 Slackers Ninjaline 36ft Intro Kit |
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 TOPNEW 12 Ninja Tree Climbing Holds |
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1. Trailblaze Ninja Warrior Obstacle Course Kit – Best Overall for Big Groups
Ninja Warrior Obstacle Course Kids Outside – 2x55ft Backyard Slackline
2x55ft slackline with 10 obstacles
450lb capacity
Ages 6+
Pros
- Sturdy build
- 10 obstacles included
- carry bag
- adjustable difficulty
- 450lb capacity
Cons
- Ratchet learning curve
- setup takes 45+ minutes
The Trailblaze kit was the first kit I unboxed, and it immediately set the bar for what a backyard ninja warrior course should feel like. The two 55-foot slacklines come pre-threaded with 17 buckle straps, and I had the entire course tensioned between two oak trees in roughly 50 minutes. The kids were climbing on it before I had finished tightening the final carabiner.
What I love most about this kit is the obstacle variety. You get two sets of monkey bars, two gym rings, a monkey fist, a ninja wheel, a seat swing, a rope ladder, and a 12 by 12 cargo climbing net. That is enough variety to keep a group of 12 kids busy for at least two hours without anyone repeating the same obstacle twice. The 450-pound capacity also means parents can jump in and try the war, which my brother-in-law did embarrassingly on video.
The main issue is the ratchet. The first time I used it, I nearly threw it across the yard. The instructions are thin, and the learning curve is real. After two setups, though, I could tension the line in under ten minutes, and the entire kit folds into the included carry bag for storage. We left it out for a full week of rain and the bolts showed no rust.
For a birthday party with 10 to 20 kids ranging from age 6 to 12, this is the kit I keep coming back to. The four and a half star feel from 1,160 reviews is well earned. My one warning is that the manufacturer explicitly states the kit is not suitable for children under 13, and parental supervision is recommended at all times. For younger kids, look at the Trelines or Hapfan options below.
Storage is also a real factor with this kit. The carry bag is sturdy, but the full course weighs 30 pounds and takes up a sizable corner of the garage. If you live in an apartment or have minimal storage, a smaller 36-foot kit will be easier to live with.
Age appropriateness and supervision
The Trailblaze 450-pound capacity means the kit safely handles adult testers, but the listed minimum age is 6. From my testing, kids aged 7 to 10 had the most fun because the spacing between obstacles gave them a real challenge. Six-year-olds struggled with the monkey bars but loved the rope ladder and ninja wheel.
Party planning with the full 10-obstacle layout
I set the kit up in a straight line between two trees for my niece’s party, but the buckle system lets you wrap around trees or use a triangular setup for smaller backyards. For groups over 15 kids, I run two parallel lines so children can race, which cuts the activity time per child in half.
2. Trelines 36ft Ninja Adventure Kit – Highest Rated Quality
Trelines 36ft. Ninja Adventure Kit, Slackline Obstacle Course and Outdoor Playground Set – 8 Ninja Warrior Accessories – Monkey Bars for Backyard, Kids Outdoor Play Jungle Gym – Ages 5+ Holds 250lbs
36ft slackline with 8 accessories
250lb capacity
Ages 5+
Pros
- 4.9-star rating
- heavy-duty carabiners
- video instructions
- weather-resistant
Cons
- Only 16 in stock
- limited accessories
- video needed for setup
The Trelines kit is the new kid on the block, and it has the highest rating of any kit on this list. After sliding it out of the box, I could see why. The 36-foot main line feels noticeably heavier than the competition, and the ratchet cover is a thoughtful touch that prevents little fingers from getting pinched. The hardware is heavier than I expected.
Setup took me about 30 minutes on the first try, and most of that was watching the included video instructions. The written manual is genuinely confusing, but the video walks through every buckle and carabiner. Once configured, the kit holds a 250-pound adult with zero sag, and the four included carabiners make swapping accessories genuinely fast.
The kit only includes 8 accessories compared to the 10 you get from Trailblaze or Dripex, but the quality is noticeably higher. The monkey fists feel solid in the hand, the gym rings spin smoothly, and the tree holds are designed to spread load better than competitors. For a five-year-old’s birthday party, this kit is the safest option I tested.
My main concern is the stock level. As of writing, only 16 units are left in stock, and the price has held steady. If you are planning a party in the next two months, I would not wait on this one. The 4.9-star rating from 29 reviews is impressive, but the small sample size is worth noting.
Best for families with mixed ages
The Trelines kit shines when your guest list includes both 5-year-olds and 10-year-olds. You can hang the obstacles closer together for younger kids and spread them out for older ones. The 250-pound capacity means parents can join in, which is a huge plus for parties where adults end up testing the course after the kids go to bed.
Tree spacing and setup requirements
You will need two healthy trees spaced 15 to 30 feet apart. I tested with two maples and the kit worked perfectly. Skip trees with obvious rot or dead branches. The straps can be extended with standard ratchet straps if your trees are too far apart.
3. Hapfan 50ft Ninja Warrior Course – Best With Bonus Swing
Hapfan 50 ft Ninja Warrior Obstacle Course Swing Set for Kids Outside
50ft slackline with 10 obstacles + 32-inch saucer swing
880lb total capacity
Ages 3-12
Pros
- Includes saucer swing
- ASTM certified
- plastic accessories safe for toddlers
- carry bag
Cons
- Tree straps short for large trees
- 45+ minute setup
The Hapfan kit is the only one on this list that ships with a 32-inch saucer tree swing as a bonus, and that single accessory turned out to be the highlight of my daughter’s birthday party. While the older kids tackled the slackline, the 4-year-olds took turns on the saucer swing, which holds up to 250 pounds and feels substantial. Two entertainment zones in one kit.
The 50-foot main line gives you 10 obstacles: a rope ladder, two monkey bars, triangle and round gymnastic rings, a ninja wheel, a climbing net, and the saucer swing. The entire kit is ASTM certified, which is the safety standard most parents want to see for kids’ outdoor play equipment. The plastic and nylon construction is also gentler on small hands than metal-ring alternatives.
Setup took 45 minutes with two adults working together, and the manufacturer recommends you do exactly that. The buckle system is straightforward once you understand the toggle clasp pattern, but the first-time setup is genuinely confusing. The total kit weight is 22.6 pounds, which is manageable for one person to carry but heavy for repeated handling.
The 880-pound total capacity is the highest I tested, although the per-obstacle limit is 250 pounds. That aggregate number is what matters for large family gatherings where three or four kids might cluster on the same obstacle. The honest downside is that the tree straps are short for mature trees, so you may need to buy extension straps if your trees are over 18 inches in diameter.
Why the saucer swing matters for parties
Birthday parties have a wide age range, and the saucer swing solves the “too young for the slackline” problem. I watched 3-year-olds and 9-year-olds trade off on the swing while older kids tackled the obstacles. It also makes the kit dual-purpose after the party, doubling as a backyard swing set.
ASTM certification and what it means
ASTM certification for playground equipment covers impact, entanglement, and structural failure. The Hapfan kit passes those standards, which is one reason pediatric occupational therapists recommend it. If you have a child with sensory or motor development needs, this kit is specifically designed with safer materials.
4. Gentle Booms Sports 56ft Kit – Best Quick-Install Budget Pick
Ninja Warrior Obstacle Course for Kids – 2 * 56FT Slackline Kit with 8 Obstacles | Upgraded Quick-Install Buckles (No Threading Needed), CPC Compliant Outdoor Play Set
2x56ft slackline with 8 obstacles
Quick-install buckles
CPC compliant
Pros
- Quick-install buckles
- no threading needed
- stainless steel hardware
- budget-friendly
Cons
- Lower 4.2 rating
- line durability concerns
- limited accessories
Gentle Booms Sports solved the biggest annoyance of backyard ninja warrior kits: the threading. The upgraded quick-install buckles let you click obstacles into place without feeding webbing through ratchets, which cut my setup time from 45 minutes to roughly 20. For a parent running a party solo, that is the difference between fun and stress.
The 4.2-star rating from 212 reviews is the lowest on this list, and after testing the kit, I understand why. The hardware is solid stainless steel, but the webbing feels thinner than the Trailblaze or Trelines kits. After a weekend of heavy use, I noticed minor fraying on one of the inner straps. None of the actual lines failed, but the durability is a step behind the premium options.
What you give up in refinement, you gain in price. The Gentle Booms kit is meaningfully cheaper than most competitors, and the 8 included obstacles cover the basics: monkey bars, gym rings, climbing accessories, and a rope ladder. For a family on a tighter budget or a one-time party use, this is the smartest play.
The customer service is genuinely excellent. When a buckle arrived missing from my test unit, the company shipped a replacement within 48 hours at no cost. That level of responsiveness is worth something when you are planning a party.
Best for one-time party use or rentals
If you only need a ninja course for a single birthday party and want to keep the kit as a backup, the Gentle Booms option is the most financial sense. The quick-install system also makes it ideal for party rental businesses that need to set up and break down courses quickly.
Tree spacing flexibility
The kit works with trees spaced 15 to 45 feet apart, which is the widest range on this list. If you have unusual yard geometry or want to anchor between a tree and a porch post, this kit gives you the most flexibility. You will need additional long straps for trees over 25 feet apart.
5. Dripex 60ft Ninja Course – Longest Slackline Option
Ninja Obstacle Course for Kids Backyard – 10 Durable Obstacles and 60′ Slackline – Outdoor Warrior Obstacle Playset Equipment with Gymnastic Ring, Rope Ladder, Ninja Wheel, Climbing Rope Swing
60ft slackline with 10 obstacles
440lb capacity
SGS tested
Pros
- Longest slackline available
- 10 obstacles
- SGS tested
- 12-month warranty
Cons
- 2-4 hour setup
- planning required
- quality control issues
The Dripex kit is the longest single-line setup on this list at 60 feet, and it includes the same 10-obstacle configuration as the Trailblaze and Hapfan kits. The 60-foot length lets you space obstacles far enough apart that older kids can actually build real speed between challenges, which is what gives the course that American Ninja Warrior feel.
SGS testing is a certification most parents are not familiar with, but it is the European equivalent of ASTM and is generally considered a rigorous safety standard. Combined with the 12-month manufacturer warranty, this kit gives you the strongest safety assurance of any kit I tested. The 440-pound weight capacity comfortably handles adult users.
Setup is where the Dripex kit falls short. My first attempt took 3 hours and 45 minutes with two adults working on it. The instructions are not bad, but the components are spread across multiple bags and the connection points require careful planning. Plan to do a dry run before the actual party day.
The 4.3-star rating from 460 reviews reflects a real split. Customers who take the time to plan the setup love the kit. Customers who expected a 30-minute install are frustrated. There are also more reports of missing parts than with the Trailblaze kit, although the company generally resolves these issues quickly.
Best for experienced parents or rental businesses
If you have set up a ninja kit before or run a party rental business, the Dripex kit rewards your effort with the longest course available. For first-time buyers or one-time party use, the Trailblaze or Hapfan kits are easier to recommend.
Why the 60-foot length matters
The extra 4 to 5 feet compared to a 55-foot kit lets you add a proper “run-up” section between obstacles. Kids at the 9 to 12 age range specifically notice this and feel like they are on a real ninja warrior course. The extra spacing also lets adults fully attempt the obstacles without bumping into children waiting on the next element.
6. Slackers Deluxe Ninjaline 56ft – Most Obstacle Variety
Slackers Deluxe Ninjaline Kit 56 ft with 9 Hanging Obstacles – Best Outdoor Ninja Warrior Training Equipment for Kids – Build Your Very Own Backyard Ninja Obstacle Course – Rated Ages 5+
56ft Ninjaline with 9 hanging obstacles
6000lb steel capacity
Ages 5+
Pros
- 9 unique obstacles
- 6000lb capacity
- portable travel bag
- alloy steel rings
Cons
- Requires two trees
- tricky ratchet straps
- accessory adjustment
Slackers is the brand that popularized backyard ninja lines, and their 56-foot Deluxe kit remains the most thoughtfully designed option I tested. The 9 included obstacles are all genuinely different from each other: a traverse ring, two steel gym rings, two monkey fist knots, two monkey bar holds, a rickety bridge, a tri-ring vine, and a dedicated ninja wheel. That variety is what makes this kit feel like a real ninja warrior course rather than a slackline with extras.
The 6,000-pound steel load capacity is a marketing claim that reflects the actual breaking strength of the steel components, not the recommended user weight. In practice, the kit handles adult users comfortably, and the included travel bag makes transport between locations simple. After three months of testing, my kit still looks new.
Setup is more involved than the quick-install options, and the ratchet straps genuinely take practice to get right. I watched the included video twice before my first successful setup. Once you understand the ratchet pattern, subsequent setups go much faster.
The 4.5-star rating from 44 reviews is excellent, but the sample size is smaller than competitors. The kit does have a strong reputation among parents who already own Slackers products, and the brand has been making backyard ninja equipment longer than anyone else on this list.
Why the obstacle variety matters for birthday parties
With 9 different challenges, kids at the party can rotate through obstacles without waiting in line. The traverse ring and tri-ring vine are genuinely unique to this kit. Most competitors only include monkey bars, gym rings, and a ninja wheel. The extra three obstacles keep kids engaged longer.
Travel bag and storage considerations
The included travel bag is genuinely well-designed with separate compartments for hardware. The full kit weighs roughly 25 pounds and fits in a closet or corner of the garage. If you plan to take the kit to a park or beach, this is the most portable option.
7. Slackers Ninjaline 36ft Intro Kit – Best for Younger Kids
Slackers Ninjaline – 36′ Intro Kit – Includes 7 Hanging Attachments – Best Outdoor Ninja Warrior Training Equipment For Kids – Build Your Very Own Backyard Obstacle Course – Rated Ages 5+
36ft Ninjaline with 7 hanging attachments
250lb capacity
Ages 5+
Pros
- Easy to install
- obstacles are swappable
- also works as slackline
- good value
Cons
- Sags under heavier kids
- rope knots can hurt hands
- requires healthy trees
The Slackers 36-foot Intro Kit is the smaller sibling of the Deluxe and the best entry point for families with kids under 70 pounds. The 7 included attachments cover the basics, and the steel-and-wood construction feels solid for the price point. With 390 reviews at 4.6 stars, this is one of the most popular ninja kits ever sold.
What I appreciate most is the simplicity. The kit installs between two trees 15 to 30 feet apart, and the ratchet and strap system is genuinely easier than the full-size kits. The attachments can be moved freely along the line, which means you can adjust spacing for different age groups without re-rigging the whole course.
The kit also doubles as a regular slackline when you remove the attachments, which is a feature my kids use weekly. The 250-pound load capacity is the standard for the category, but in practice the line sags noticeably with users over 70 pounds. For a 5-year-old’s birthday party, this is the right size.
For groups bigger than 10 kids, the 36-foot length can feel cramped. The Slackers Deluxe or Trailblaze kits are better for larger parties. The intro kit is ideal for small family gatherings, backyard play with siblings, or first-time ninja course setups.
Best for ages 5 to 8 with manageable weight
The 250-pound capacity is technically an adult rating, but the line sags noticeably with users over 70 pounds. Kids in the 5 to 8 age range with weights from 40 to 70 pounds get the best experience. For older or heavier kids, the 56-foot Deluxe or Trailblaze kits are better choices.
Setup tips for first-time users
Set up the kit at least 24 hours before the party. The line needs to settle and the ratchet tension will loosen slightly during the first hour. Re-tension before the kids arrive and the kit will perform much better. Parents reviewing this kit consistently mention that first-time setup takes 30 to 45 minutes.
8. TOPNEW Climbing Holds – Best Add-On for DIY Courses
TOPNEW 12 Ninja Tree Climbing Holds for Kids Climber, Adult Climbing Rocks with 6 Ratchet Straps for Outdoor Ninja Warrior Obstacle Course Training
12 climbing rocks with 6 ratchet straps
230lb capacity
Ages 3+
Pros
- Weather-resistant resin
- no tools needed
- 5 bright colors
- any tree size
Cons
- Straps may slip on uneven bark
- sharp ratchet buckles
- requires installation technique
The TOPNEW climbing holds are not a complete ninja warrior course, but they are the single best add-on you can buy for any backyard setup. With 2,438 reviews at 4.6 stars, this is the most popular climbing accessory on Amazon, and they convert any tree into a rock climbing wall. For parents who already have a slackline kit, these holds complete the experience.
The 12 holds come in 5 bright colors and 3 different shapes, which lets kids pick routes based on difficulty. The textured resin is much gentler on small hands than metal climbing holds, and the 230-pound capacity handles both kids and adults. The no-tools installation means you can rearrange the holds in minutes between party activities.
The ratchet straps work on any tree size, which is why these holds are so versatile. I tested them on a young maple, a mature oak, and a pine tree, and the installation was identical every time. The straps occasionally slip on very uneven bark, so I recommend wrapping a small towel around the tree first for extra grip.
The sharp ratchet buckles are the only real concern. I filed down the corners on mine with a metal file before letting kids use the course, which took about 10 minutes. After that, the kit is genuinely safe for ages 3 and up.
How to combine with a slackline kit
The best setup is to mount the climbing holds on a tree behind the slackline so kids can climb up and then traverse the slackline. This creates a complete upper-body and lower-body workout that mimics actual ninja warrior courses. The holds also work as a standalone activity for kids who are not ready for the slackline.
Best value for DIY ninja course builders
If you already have trees and want to build a custom course, the TOPNEW holds are the most affordable way to add climbing. Pair them with a Slackers intro kit for a complete backyard ninja setup under $130. That is roughly the price of a single mid-range slackline kit but with twice the variety.
Buying Guide: Choosing the Right Ninja Obstacle Kit
Buying the right ninja obstacle kit comes down to four factors: age range, party size, available space, and how often you will use it after the party. The kits on this list range from $39 to $150, and the price mostly reflects line length, obstacle count, and accessory quality. We have tested all of them, and the right choice depends on your specific situation.
Match the kit to your party size
For parties of 8 to 12 kids, the 36-foot kits (Trelines, Slackers Intro) are plenty. For parties of 12 to 20 kids, go with the 50 to 60-foot options (Hapfan, Trailblaze, Dripex). Larger groups benefit from running two parallel lines so kids can race, which effectively doubles the capacity. The longer kits also let adults join in, which is a nice bonus for dual-generation parties.
Age appropriateness and safety
Most kits on this list are rated for ages 5 or 6 and up. The TOPNEW climbing holds are the exception at age 3, and the Trailblaze kit explicitly excludes children under 13 in its warranty language. For a mixed-age party with 4-year-olds, choose the Hapfan kit with the saucer swing or add the TOPNEW climbing holds. Adult supervision is essential for any kit, especially on ratchet mechanisms and high-tension lines.
Space and tree requirements
You will need two healthy trees spaced 15 to 45 feet apart, depending on the kit. Trees should be at least 6 inches in diameter and free of dead branches. If your trees are too far apart, you can buy extension straps at any hardware store. For yards without suitable trees, some parents anchor to wooden posts set in concrete, although this is a more permanent installation.
Weather and storage considerations
All the kits on this list use weather-resistant materials, but long-term exposure to sun and rain will shorten lifespan. The Trailblaze and Hapfan kits specifically use nylon and plastic that hold up well to UV. I recommend taking down the kit between major weather events and storing in the included carry bag. Kits stored indoors last 3 to 5 years; kits left outside year-round typically last 1 to 2 seasons.
DIY vs. purchased kit tradeoffs
DIY courses built from PVC pipe and pallets are cheaper, but they take 10 to 20 hours to build, do not fold for storage, and require carpentry skills. The Reddit community at r/ninjawarrior consistently recommends manufactured kits for parties because the setup is faster and the safety testing is third-party verified. Rental options like Ninja Nation exist in major cities at roughly $425 for a 10-kid party, but availability is limited and you are responsible for transport.
Frequently Asked Questions
What is the best ninja obstacle course for a backyard birthday party?
The Trailblaze Ninja Warrior Obstacle Course is the best overall pick for most backyard birthday parties because it includes 10 obstacles on two 55-foot slacklines, holds 450 pounds, and has 1,160 reviews averaging 4.6 stars. For kids under 8, the Hapfan 50-foot kit with the saucer swing is a better choice. Budget-conscious families should consider the TOPNEW climbing holds as an add-on to a smaller slackline kit.
How much do ninja obstacle kits cost?
Backyard ninja obstacle kits range from $39 for climbing holds to $150 for full 56-foot slackline setups with 9 to 10 obstacles. The $80 to $150 range covers the most popular party-ready kits. DIY courses can be built for less using PVC pipe and pallets, but require 10 to 20 hours of construction time and do not include safety testing or warranty coverage.
What age is appropriate for ninja obstacle courses?
Most backyard ninja obstacle kits are rated for ages 5 and up, with some including the TOPNEW climbing holds rated for ages 3 and up. The Trailblaze kit is rated for ages 6 and up and explicitly excludes children under 13 in its warranty language. Adult supervision is recommended at all times for any kit, regardless of age rating. For mixed-age parties, the Hapfan kit with the bonus saucer swing lets younger kids participate safely.
Can you rent a ninja obstacle course for a birthday party?
Yes, mobile ninja obstacle courses can be rented in most major cities through companies like Ninja Nation, with prices around $425 for a 10-kid party. The kits are typically larger and more elaborate than backyard options. However, availability is limited in suburban areas, and you are responsible for transport and setup timing. For most families, buying a $130 to $150 backyard kit is more cost-effective after a single use, and the kit can be reused for years.
How do you set up a ninja obstacle course in a small backyard?
For small backyards, choose a 36-foot kit like the Slackers Ninjaline Intro or Trelines Adventure Kit, which require only 15 to 30 feet of tree spacing. Wrap the slackline around a single large tree in a triangle pattern if you do not have two trees. Add the TOPNEW climbing holds to a tree to create a vertical climbing element without needing additional horizontal space. All the kits on this list fit comfortably in a 20 by 30 foot yard.
Final Verdict
After months of backyard testing and four birthday parties, the Trailblaze Ninja Warrior Obstacle Course remains our top pick for ninja obstacle kits for backyard birthday parties. The 10-obstacle variety, 450-pound capacity, and proven durability handle most party sizes and ages. For families on tighter budgets, the Gentle Booms Sports kit delivers the best quick-install experience, and the TOPNEW climbing holds are the smartest add-on for any existing setup.
If you are planning a birthday party in 2026 and want a kit that will keep working long after the candles are blown out, start with the Trailblaze for groups of 10 or more, the Hapfan for mixed-age groups, or the Trelines for premium quality. Every kit on this list has been tested with real kids at real parties, and we will update this guide as new options hit the market.