First you need to source the parts.
You could use other wooden sticks but barbecue bamboo sticks are great, they are long, light, strong, flexible, and cheap. I bought 150 sticks for one british pound (~1.5 $) at the corner shop.
The magnets are coming from Firstformagnet.com
, they were the cheapest one doing next day delivery in the UK.
For USA delivery, you can get them here really fast : http://www.getbuckyballs.com
I use sugru
: 8 coloured mini-packs in a lovely large pouch, each mini pack allowing me to coat at least 4 single heads.
£ 16.66 (~$ 25) : SuperCool GunMetal Magnet Xtreme Neodymium Puzzle 1 Premium N42 Official 5mm Size Spheres
£ 12 (~$ 18) : Sugru Multi-color 20g x3 and had 2/3 of sugru extra for other fun projects!
£ 1 (~$ 1.55): bamboo sticks
Total : £ 29.66 (~$ 46.10) for a set of 28 sugru magnetic construction set sticks, but I could have made 3 times more sticks than that. I believe it shoudn't be too hard to make it cheaper than that.It took 2 of us about 2 hours to make, dried over night and was ready to play with. I think it is also possible to work faster.
First you want to cut the wood sticks to size. Because we are cutting many small things, I highly recommend using a metal saw (small teeth) to have a rather clean cut and avoiding cutting yourself. Wear gloves - not like me :)