Sorry about the previous empty post. You might consider the Bogan/Manfrotto monopod 3245 ($72 U.S. from B&H). This unit consists of three telescoped pieces. There is a handle near the top of the upper piece that can be grasped in one hand and used to control height of the top two pieces. With the bottom piece telescoped inside the top two, height of the unit can be varied from 27 to 46 inches (not counting height of what ever head you put on it). Height of all three pieces can vary form 26 to 64 inches; however, control of the bottom piece requires two hands.
I have not tried this rig on photographing children but I have found it to works well on zoo animals and small, wild critters (neither to be confused with young, small humans). I find this monopod easier to operate then one where you have to shift your grasp to locate and turn a knob (which I almost always try to turn the wrong way first) while trying to steady everything by holding either the camera or the monopod. For me, the movement of changing height is smoother and more controlled and less time is spent fumbling with everything. George Baumgardner P.S. A down side to this model is that it looks even more like a police impact weapon (baton) then most monopods so you would be even less likely to be able to carry it on plane.
