4M Water Rocket Kit, DIY Science Space Stem Toys, For Boys & Girls Ages 8+

Very fun for all ages - adults liked playing with it as much as the kids. Works great. "A good time that was had by all". Comes with - 2 rubber cork plugs - 2 sets of 3 fins (and a spare fin for each set, tho they seem pretty durable, no breaks yet) - 2 plastic air tubes to connect tire pump to rubber cork in water bottle. - 4 small plastic connectors for connecting tire pump to the rubber cork via clear plastic tube (basically, one connector thru rubber cork, connect clear tube, another connector for bike pump; 2 sets) Minimal assembly: Insert tire pump connector thru the rubber cork provided so it sticks out thru wider part of rubber cork (only goes 1 way, cant mess it up) Connect clear plastic tube to connector on rubber cork, and insert other small connector into the other end of the clear tube to connect to tire pump (basically, 1 connector for each end of clear tube). Fill water bottle 1/3 full with water. Press the rubber cork into bottom of bottle. Press HARD. The harder you press it in, the more pressure is needed to pop it out and the higher it will go. Stand rocket up on fins as its launch pad. Start pumping the bike tire pump until the cork pops out and the rocket launches. (While reading about these bottle rockets, I could never figure out what the release mechanism was to actually launch the rocket - turns out its a function of how tightly you insert the rubber cork, thats it). We were launching 200-300 feet in the air once we figured out we just need to push the rubber cork in harder. While you can use any 1 liter bottle, I prefer the Seagrams Tonic 1 liter bottle - cuz then I have an excuse to make Gin & Tonics too! However, the Polar brand Tonic bottle is more streamlined, looks more like a rocket. And you can cut the top off another bottle to attach it on top of the main engine bottle for a bigger rocket, and a more streamlined look. (pointed nose vs flat bottom of main bottle on top) Google around and you will see examples.

This is a pretty great kit, especially for the price. It was pretty easy to build, in fact I was able to let my daughters do most of the steps, and we had it together very quickly. The fins are pretty heavy-duty and haven't broken yet, even after many flights and landings; I've been careful to make sure that the fin assembly gets screwed on by the center fitting, though, rather than using the fins themselves as levers - I think that might break them. An extra fin was included. I was disappointed at first that there's no specific release mechanism - you just wedge the plug up into the mouth of the bottle, and pump until it lets go. However, this turns out to be part of the fun of the process, as you never know quite when it will take off; it also lets you change up how high it goes (and how hard it is to pump up) by how hard you jam in the plug. (That is, for my younger daughter, I could put it in relatively gently - or let her put it in - and it would let go at a lower pressure, which was within her ability to pump it up.) It can go quite high, probably 100 feet on a good shot - we have done most of our shooting from the middle of a golf fairway in order to have enough space. Now, if you're handy, you could build this from parts in a hardware store and an hour or two at your workbench - but the fitting on the plug is actually pretty clever in its design (so that the pressure tends to make the hose more secure rather than blowing it off), and the fin assembly is hardy but easy to disassemble and reassemble. All in all it's great fun and a worthwhile buy.

My daughter had to make a volcano for a school project and this is the one that we chose to use. It comes with a 4 piece mold that has to be assembled, plaster of Paris, rubber bands (to hold the mold together), and paints and paper cut-outs to decorate the completed volcano. It also comes with an eruption chamber that stays in the volcano so that it can be made to "erupt" with baking soda and vinegar. The mold is small and rather flimsy and snaps together and the kit comes with two rubber bands to help hold the mold together once it's filled with the plaster of Paris. We opted to also add several metal paper clips as well. Even with the extra clips, several small gaps were present and we wound up having to file off the seams with a fingernail file once it was dry. We mixed up the plaster but I knew (from previous product reviews I had read on here) that it wouldn't completely fill the mold. We had purchased a small box of plaster mix and added it to the mix that came with the kit and so we then mixed up enough to fill it up. Next we added the plaster of Paris to the mold until it was completely full. Be sure to gently tap the mold several times to get it around the eruption chamber. We tapped it several times but still wound up having a spot at the top that did not have any plaster. Once the plaster dried completely my daughter removed the mold and it came out almost perfect. We wound up having to mix up a little more plaster to fill in the blank spot at the top. My daughter then painted it and we attached it to a sturdy piece of cardboard with double stick mounting tape. The mold and chamber can be reused if needed, so we've put it up for my younger daughter to use next year. Overall, for the price, it's a good value and I'd pick this one again.

I bought this kit for my mom and I (my mom is 60, I'm 37) and we spent 2 winter evenings building volcanoes. The kit comes in a surprisingly small box, that's because the volcano mold is made of 4 panels that snap together. The kit includes the 4 volcano panels, a volcano chimney, a small bag of plaster, and watercolor paint. The panels and chimney are made of strong plastic and will not break. It was not a completely trouble-free experience, the amount of plaster provided is not quite enough and does not allow for mistakes. Sure enough, we made a mistake on the first attempt, we waited too long between mixing the plaster and pouring it in the mold, and ended up with a mess. The solution was to go to the local store to buy a box of plaster of Paris, which allowed to make 2 volcanoes without worrying about running out. After pouring the plaster and letting it set, the mold is taken apart to reveal the "cracked" surface of the volcano, which looks nice. The chimney remains inside, that's where the mix of soda and vinegar will go. That means the kit is not intended for making more than one volcano at a time. That was a small problem to address when making the second volcano, I cut out the spout of a water bottle and used it as the chimney for the other volcano. Worked well. Once both volcanoes have hardened and dried, then came the arts part of the project: using the watercolor, make the while plaster look like a volcano. The colors include red, yellow, blue and green, and by mixing colors one can figure out how to make the desired colors. My mom and I had different styles, I went for a more authentic look with brown and green at the bottom, and orange "lava" at the top, and my mom went for a more hippie-looking volcano. They both looked great. The finished volcano is about 5 inches tall. Since we were planning on filming and photographing the volcano eruptions, we did some experimenting with soda and vinegar in the sink using small glasses. We figured out the quantities we liked, and added some food coloring to make the lava orange instead of a white foam. The result was fantastic. And then came the fun part: it was winter time in Canada, so we put the volcanoes on newspaper and the newspaper on the snow, took plenty of pictures (there were plenty of pictures at every step of the project as well), then proceeded with the eruptions. The whole family was outside to attend. They were spectacular, the lava erupted and flowed down the mountain... We had a great time with this kit, and apart from the limited quantity of plaster it is good quality and well made. That would be a fun thing to do with kids, there are several skills involved in building and painting the volcanoes, and making them erupt. Highly recommended.

The rocket is a fun activity for sure. The assembly was very easy and the operation is very simple. I don’t have a hand pump so I used a batter operated one and it works really fast! It would be great for a science project, learning about the pressures, water levels, and bottle sizes. How they correspond to height of the bottle on launch. It’s a good transition into model rockets too. Recommend for sure, but if you are really going to use differing equipment, it might be a good idea to get a longer tube for the air. You can pick them up from any hardware store. Electric pump with digital pressure or preset limit would be best for more precise experiments.

Kids love it!

It broke after only a few launches. It was fun until it broke. It does go very high. It can with an extra fin but the fin is not what breaks when it hits the ground so that didn’t do us any good.

I bought this to use with my 3 year old and she loves it. Very easy to put together and she had a blast every time it launched. It comes with the bottle, screw for the bottle, the fins, 2 adapters for the bike pump, the tubing, and the plug for the bottle. After a quick setup and a little water, we were good to go. You just put a little water in the bottle, plug the end, then pump the bicycle pump about 3-5 times. We used a pump that you can put both feet on while you are pumping. The launch requires 30-40psi depending on how much water you put in it. Once you get the right pressure, it launches and uses the water as its propulsion. Just like the box says, it does launch about 30 meters high (90+ feet). The instructions also included a couple paragraphs explaining the science behind the kit (action v reaction). I thought this was pretty neat. It never hurts to learn something while having fun. We had asphalt and concrete nearby so the bottle and fins did get scratched when they landed on either one of those. Otherwise, I think you can get hours and hours of fun from just the one bottle without it wearing out. We will probably be testing out some different bottles to see if there is much of a difference in the launch or flight. I'm also thinking the bottle needs some tape for weight at the top so the fins don't hit the ground first. I was worried it would use a bunch of water and the fun wouldn't last long. However, we filled up a gallon jug and that was good for about a dozen launches or more. Overall, I would highly recommend this product. Yes, you can probably make it yourself, but for a ready-made kit, this is well worth the cost. The kit is meant for kids 8+, but it is definitely a fun thing for younger than that if there is proper supervision. Unfortunately, my 3 year old could only pump a few times before the pressure was too high, but I don't see older kids having any trouble with it.