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

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.

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.

We purchased this and had a great evening while we were building it. Make sure to put something down before starting because there will be some mess

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.