Water Rockets!

Water rockets are a crazy fun activity for your Pack.  We used our rocket derby as a recruiting event.  We came prepared for over 100 rockets.  We placed an event notice in the local paper.  And we spread the word through the boys at school.  It was a LOT of fun and we signed up several new scouts, and even a couple new leaders.

There is an initial investment to aquire your launch systems, and rocket supplies.  Some things you will already have kicking around in your garage.  Others you will have to purchase.


  • Rocket Launch Pad – There are plans on the internet for constucting the launch pads.  But I went straight to the source!  Water Rocket Pop is the place to go.  The new design with the internal seals works great with a wide range of bottles. 
    • When you place your order, tell Mike that you want dual air connectors for bike pumps and compressors. 
    • If you want to run more than one launch pad you will want to construct a launch control system like the one pictured above.  All the fittings and the pressure gauge (essential) will run about $80.
  • Air – You have to have a method for compressing air.  If you are going to run an event for a pack, a small air compressor is priceless.  Otherwise, start collecting bike tire pumps.  Our experience with bike pumps has been pretty poor.  They are typically not up to the abuse they get on the launch pad.  I would love to engineer a bike driven air compressor for a future event…
  • Water – You will have to either have a source close to your event, or bring your own.
  • Bottles – Of course!  You have to have plastic bottles! 1-2 per person.
    • You MUST use bottles from carbonated beverages.  16-20 oz. soda or sparkling water bottles work really well.  Test that they fit the launcher prior to your derby!  A small percentage of bottles will not fit down over the launch tube.
    • Put a call out to the Pack a few weeks ahead of time for bottles.  You should be able to collect enough over a few weeks time.
    • If you use regular water bottles, they will EXPLODE.  The plastic is too thin and will burst.  And at 50-60 PSI the sound is VERY loud.  Not good for the ears if you are too close.
    • You can also make some big rockets from 2 liter bottles!  I would use these as show pieces or intermission launches while everybody cools down in the shade and drinks some water.
  • W I D E  O p e n  S p a c e – You will be amazed at how far the rockets can travel.  When constucted properly and with about 80-90 PSI, you will get some serious air time.  And if you are in breezy conditions, they will travel down range with the winds.  So be sure to plan for that.  Normal powers of observation rules apply:
    • No power lines!
    • Watch for potential personal property interference – You do not want to be climbing fences to retrieve rockets from backyards and swimming pools.
    • To many people in the launch area, or potential landing zone, etc. 
    • If using a public park you may need a permit or need to register with the local parks and rec. 
    • Don’t forget about your tour permit!
  • Construction Space – Either existing picnic tables, or folding tables that you bring.  Figure 4 rockets can be constructed per table, max.  You don’t really need chairs.  Encourage attendees to bring their own folding chairs.
  • Rocket Materials – We already covered bottles above. 
    • Poster Board – Use to form the rocket tube, fins, and nose cones.  The size will depend on what you can find.  We got ours in the Bay Area at RAFT which is the Resource Area For Teachers.  RAFT is also open to Scout leaders.  They have lots of neat project supplies, but you have to go in with an open and creative mind.
    • Packing tape – Lots and lots of packing tape.  Just head on over to the local big box office supplies place and grab a case.  You can always use it for other Pack activities. 
    • Pens and markers for decorating.
    • Scissors – Several pairs comes in handy.
    • Fins – 3 per rocket.  Fins pre-cut before event.  Templates are available in Wesley Wongs water rocket Pow Wow handout.
    • Nose cones – 1 per rocket.  Also pre-cut before event. 

My family helped trace out all the fins and cones onto poster board over a weeks time.  Then we held our Pack Leader meeting in my garage.  Everyone brought a pair of scissors and we cut out nose cones and fins during our meeting.