With just a USB stick and a portable hard drive or SD card, teachers of primary through secondary courses can provide their students a consistent learning experience, in and out of the classroom. The Lernstick (learning stick) distribution [1] is a slightly modified Debian 7 Live system with numerous educational programs aimed at different ages, including the 3D Marble Virtual Globe, the computer game TuxMath, a vocabulary trainer named Parley, and the music notation program Reunion (Figure 1).

Figure 1: Lernstick comes with numerous well-known programs from a variety of disciplines, including the music notation software Reunion.

School Days

A lack of education funding means that schools are rarely able to provide their students with computers. Instead of sending parent teacher associations begging, the students could bring their own laptops to classes. This also offers the advantage of being able to continue working at home with the same device.

However, you cannot assume that the same operating systems and the same applications are running on every single device. That's why the counseling service "Digital Media in School and Teaching" (imedias) of the University of Applied Sciences and Arts Northwestern Switzerland (FHNW) created the special Lernstick distribution.

Lernstick does not touch the operating system on the hard drive of the computer, and files and documents created during the day end up in a separate partition on the disk with the Live system.

Besides the learning programs, Lernstick includes traditional office software like GIMP, the Iceweasel browser, and LibreOffice office suite. Also on board is the program iTalc [2], which helps teachers organize classwork and access their students' computers.

A list of programs on the Internet refers to an out-of-date version of the system from the year 2010 and is therefore largely worthless [3]. However, you can install any packages from the Debian repositories.

According to developers, Lernstick requires only a computer with an x86 processor and 250MB of main memory. However, these resources prove to be unrealistic in most cases: LibreOffice alone needs around 1GB of main memory.

In addition to the regular system, a special variant exists for exams, which blocks access to the network, devices for wireless data transmission, and storage media. This makes it difficult for students to copy from the Internet during a test, although the teacher can allow students to share individual websites on a whitelist. The teacher also determines which programs students are allowed to use.

Jump Start

FHNW provides the standard (Standard-Lernstick-System) and testing (Lernstick-Prüfungsumgebung) distributions free of charge as ISO images [4]. The standard version is almost 4.3GB in size, whereas the exam version weighs in at 2GB. You first burn the image to a DVD and boot the system. Special tools within the Live system transfer the required files to a USB stick.

If you are worried about setting up your flash drive, you can order a ready-to-run imedias USB stick [5]. However, the provider asks for a whopping 80 CHF (Swiss francs) for a 16GB flash drive with the system for shipping abroad – this corresponds to around EUR 65 (~US$  90).

After starting the DVD, a menu appears (Figure 2); you can use the arrow keys to navigate and press Enter to confirm the selection. Your first stop should be the Language line, where you define the user interface language and the keyboard layout. Lernstick assumes a standard PC keyboard; key assignments for MacBooks are set up later in the Live system.

Figure 2: If you do not press a button within 10 seconds, the Live system automatically starts with default settings, which are not always the best choices.

Besides German, Lernstick also supports English, French, Swiss, Italian, Spanish, Brazilian Portuguese, Albanian, and Russian. Not all preinstalled programs, however, are completely translated, some speak a mixture of your target language (if not English) and English. That said, more language packs are available in the repository.

By default, the system boots into a KDE environment, which can greatly facilitate the move for Windows users, or you can enable an alternative desktop in the Desktop menu item. The choices are Gnome 3, the particularly resource-saving Xfce and LXDE desktops, a pure text console, and Sugar [6], a user interface optimized for children.

Sugar simply provides a few predefined programs from which to choose, including an IRC client and a web browser (Figure 3). These programs let students participate in arbitrary chats and access any website. Teachers will probably want to modify the stick before use.

Figure 3: Clicking one of the icons launches the matching application in the Sugar interface.

Lernstick basically starts a 32-bit, version 3.12.0 kernel, which, although it even runs on older computers, uses a maximum 4GB of main memory. If the system has more RAM, you will want to enable the More than 4 GB of RAM item below Advanced Settings. Then, a PAE-enabled kernel is used that makes full use of the main memory.

Writing Tools

Selecting Start Lernstick takes you to the Live system. If the boot process is slow, you can select Advanced settings  | Show start-up messages in the menu. Debian 7 logs the system startup and any problems.

On first start, the system indicates that you still have no option for saving documents and settings. After clicking OK, the software Storage media management tool appears (Figure 4), where you select to install the system on the storage media.

Figure 4: Storage media management not only installs Lernstick on a USB stick, it can repair a broken system, among other things.

Now insert the medium on which you want to install Lernstick, click Next, and select the disk in the list at the top. If it does not have enough space, the wizard displays a gray bar with the words Too small.

If you want to install Lernstick on a hard disk, check the box in front of show hard disks (top right corner of the dialog) and select the desired drive from the list. A word of caution: In each case, the wizard deletes the entire disk. Existing data is irretrievably lost.

To store the files students create, as well as changed settings, the wizard creates a separate data partition. Its size is illustrated by the green bar in Figure 5. The wizard formatted this partition with the ext4 filesystem, which means students cannot access the data from Windows or Mac OS X without detours. For this reason, you need to create another partition for sharing. The size is set with the slider in the Exchange partition (optional) tab.

Figure 5: The wizard has found a USB flash drive (Spaceloop XL), on which it sets up Lernstick on request.

In the upper pane, this area is shown as a yellow bar. Assign a unique Label via the corresponding dialog item, and select a filesystem format. (If the instructor gives exchange partitions different names [e.g., student names], it is easier to assign the sticks.) The default exFAT is compatible with Mac OS X version 10.6.5 and later; the other options are FAT32, which does not allow files larger than 4GB, and NTFS, which only allows read access for Mac OS X.

After you have checked all the settings, click Next, then let the wizard erase the volume. For a USB stick, you just need to click Yes; when installing to disk, you need to type Overwrite hard drive. After clicking OK, there is no turning back. When using this partition, you must keep a few points in mind (see box "Data Sink").