However, I'm not aware if there's any concrete rule for knowing which method is the best beforehand, since the difficulty of methods is subjective in the first place.

Also, my daughter kept letting go of the rubber band after the bird landed, so I tied some beads onto each end of the rubber band to keep it from falling out of the straw. I like more the effect of the wooden toy shown before it, but if you are not convinced in making it, this papercraft one should be easy enough to start with.Estoy guardando tus ideas para cuando mi hija sea un poco mayor (ahora tiene 19 meses), pero no he podido resistirme a hacer el pájaro carpintero. Joel from Made by Joel created his beautiful woodpecker printable and now gives us another colourful printable bird. For the record, the Woodpecker toy consists of a rod (static) on which a sleeve (ring) is connected. The tumbling acrobat consists of an action figure and two small bars, and he flips over when you squeeze and release the poles. because though you should end up with equivalent solutions from all methods, it's frequently found that one of them gives you a particularly easy procedure.

Artist Hazel Terry recently told me about Science Toy Maker, which is a site run by a brilliant technology educator and filled with great toy projects including this oscillating woodpecker. I showed my kids the video of the woodpecker last evening, and my four-year-old watched it over and over and over. The instructions on the linked page are really good and detailed and don't forget there are free patterns you can use.

El mío picotea mejor cabeza abajo que hacia arriba, pero he disfrutado mucho haciéndolo, me encanta jugar con él. Kyle Kanos and Chair: Firstly I am intrested in how to derive them, that was the question, because now I really don't have an idea why the equations hold. For more detailed instructions and to learn the physics of how this works, check out the Science Toy Maker post here. We made the woodpeckers this morning, and I wrote about it and posted a little video over on my blog at http://r8chel.