adjusting their engagement, they would not be told about the time factor and instead would be asked to give each object a completely subjective rating based on a scale of one to five stars.

Now we had the idea and a good working definition; all that remained was to work out a budget and parts list. The Arduino runs about $35, so we decided on a budget of $75, leaving $40 for parts. Some of that would be eaten up by nonnegotiable items like the USB cable necessary to program the Arduino, a

9-volt battery, a battery clip, the box the parts would all fit in, and tools each team would need to work with. Whatever was left had to sustain the creative needs of the designers within the technological capabilities of the system.

The folks at MAKE enthusiastically agreed to loan us workbenches and to supply some covetable MAKE items to supplement the grand prize.

With the challenge established, we refined the parts list. Since the idea started with the Arduino, that’s where we started as well. We knew we needed some forms of packaging that would accommodate the circuit board, a breadboard, and at least a battery. None of the traditional electronics project boxes had the tactile aesthetics we wanted, so we looked elsewhere for suitable alternatives. We found them in the aisles of Ikea: plastic dishware and food storage containers in lots of colors, shapes, and sizes — all easy to hack with a drill and a box cutter.

Then there was a series of thought experiments about what kinds of experiences could be built into these containers. Holding the plastic cups and boxes in our hands, we said things like, “You could put switches here and here and a couple of lights to make a puzzle. What about a little R2-D2 thing that makes beeps and chirps? Wouldn’t it be cool if ...?”

That got us to a list that we separated into input and output capabilities. With only four hours to learn to program the Arduino, build the object, and wire it up, we decided to eliminate the more exotic items that required sophisticated development and focused on collecting reliable and fault-tolerant components — switches, lights, speakers, and a little motor normally used to make cellphones buzz. For fun we added three-color LEDs that could, with a little extra effort, be made to shine in almost any color, and a couple of photosensors that would be easy to connect to the analog inputs of the Arduino.

The switches and some of the LEDs were bought in bulk 100-piece grab bags, so rather than risk giving

TOP: Senior Director Winston Hendrickson is perplexed by the stimulus/response mechanisms in the electric mushroom. BOTTOM: The plasticware proves tougher than expected and the supplied box cutters are abandoned for a turn at the soldering stations.

one team better parts by accident, we put poker chips in each box that could be traded for parts from a common table. One chip bought exactly one switch, light, cup, straw, plate, or box. We were feeling generous, so teams could take a whole handful of the little plastic beads and assorted doohickeys.

We also allowed teams to barter with each other, or trade a part they didn’t want for one they did (as long as it was available on the parts table). No intrinsic valuation of parts was made and a strict one-for-one basis made for some interesting trades: one toggle switch for one red straw, one possibly burned-out LED for one lime-green bowl. Many suggestions were ignored about establishing a currency that valued the multicolored LEDs higher than the invisible infrared LEDs. The uncomplimentary lighting in the room resulted in wholesale dumping of the photosensors, while the pressure switches were surprisingly popular.

To prepare for the event, we filled each box with

Make: 45