Before I forget, a big "Thank you" to Simon at Paddox Cycles for providing us with the old inner tube valves we needed to set up four launch pads. We really appreciate your support: without it we'd have been standing around waiting in the wind and rain.

Year 2's Flight topic moved from the pneumatic Stomp Rockets to an investigation into the forces involved in jet propulsion. The children varied the amount of water being thrown out the end of their bottle rockets and how that affected the distance it travelled. With so many other variables (pump power, wind resistance), it was hard to keep it a truly fair test, but we tried to be as scientific as we could. Sending the Wright Brothers on a balloon rocket zipwire proved a different challenge: blowing up balloons isn't as easy for young lungs, it seems...

Particular congratulations to the two engineers who brought in bottle rockets they'd made at home. With the half-term holidays approaching, if you'd like to try making your own at home you can follow the same instructions I did on the BBC's Bang Goes the Theory website.