If you have a "LCD Keypad shield" with the Arduino board, it makes possible, by using the appropiate sensors, to detect different physical variables and monitorize them on the screen.
The point is to evaluate the results without to be connected to the computer, and for that you only need a battery of 9V to power the board and the shield, so what about to create a special case to joint everything in a portable solution?
After have taken the mesures of each element, we decided to divide the interior part of our case in three different compartments to place the shield, the sensors and the battery.
But to make possible to continue seeing the pins where the sensors are connected and the screen, we have designed some windows on the top part. Another holes are in the lateral side in order to acomodate the different wires, and of course, we facilite in the bottom part the connection with the battery and the USB cable from the computer.
A freeware program called FreeCAD allows us to create the two pieces of the case, and after convert the drawings to .stl files. Then we opened this in a slicing software like SLIC3R to prepare the documents in G-code format to send them to the 3D printer.
This is the final result of our case, so you can watch some videos of demostration in the "Science with Arduino" subpage.