**5.1 Need of the next generation CRS**

Actively engaging students in classrooms is always a challenge to the teachers (Smith, 1996; Zhang, 1993). People have tried various ways to improve the interactions even from the early days of chalk and board (Bransford et al, 2000). Choosing a volunteer from raised hands and picking a name from the roll book of the class are two most common traditional methods. However, these methods only give teachers feedback from a small fraction of the class. The sample is often not typical or representative. Many students will not volunteer for fear of public mistake and embarassment. As the result, a small vocal minority will skew the view of the teacher of how the entire class understand the topic (Caldwell, 2007). To increase the sample size, people also tried methods such as shouting the answers, applause, or response cards (Karen et al, 2001), all with their pros and cons. More recently, computer based technologies are introduced to classrooms. They enabled teachers to explore more options (Patten, 2006; Richard et al, 2007; Roschelle, 2003).

The first technology used is computer-based visuals such as Powerpoint (Anderson, 2004; Bannan-Ritland, 2002; Liang et al, 2005). It has become ubiquitous today, but with mixed results. The slide shows help to provide strong graphical impact as "one picture worth a thousand words". However, the interactions and feedbacks from the students are still greatly limited. Sometime, the situation is even worse when the light is dimmed to improve the visual contrast.

Recently, a small gadget called Clicker, or the first generation CRS, is gaining momentum among teachers throughout the K-12 and higher education, and to anywhere with a group of audience (Nicol et al, 2003; Siau et al, 2006). A clicker is a remote-like device that comes with a number of buttons and a wireless transmitter. After the instructor giving out a multichoice or true/false question, the students punch the buttons on their Clickers to select their

Comparing with the force sensing of traditional touch screens, the virtual force can give a much greater force range. The depth of the action space can be easily adjusted by the virtual boundary. By using cameras with wide viewing angles, the action space can be large enough to yield many interesting 3D motions, which can be important for active computer games or on screen calligraphy or painting. Currently, the pull, push, or similar motions are absent in

Further, the users do not even need to physically touch the screen. As long as the pointer or finger is in the action space, its movement will be monitored and reflected on the movement

**5. Touch screen in the next generation Classroom Response System (CRS)**  As we explained earlier, optical touch screen described in this article is simple to implement, inexpensive to equip, and not sensitive to the wear and tear due to the pointers scratching on the touch screen. A commercial version of this device can be used to superimpose but not obstruct the existing writing surface. This makes it ideal to be used on non-traditional displaying applications, such as a whiteboard, desktop, or even a regular writing pad. Here we will briefly introduce our application of touch screen in the next generation Classroom

Actively engaging students in classrooms is always a challenge to the teachers (Smith, 1996; Zhang, 1993). People have tried various ways to improve the interactions even from the early days of chalk and board (Bransford et al, 2000). Choosing a volunteer from raised hands and picking a name from the roll book of the class are two most common traditional methods. However, these methods only give teachers feedback from a small fraction of the class. The sample is often not typical or representative. Many students will not volunteer for fear of public mistake and embarassment. As the result, a small vocal minority will skew the view of the teacher of how the entire class understand the topic (Caldwell, 2007). To increase the sample size, people also tried methods such as shouting the answers, applause, or response cards (Karen et al, 2001), all with their pros and cons. More recently, computer based technologies are introduced to classrooms. They enabled teachers to explore more

The first technology used is computer-based visuals such as Powerpoint (Anderson, 2004; Bannan-Ritland, 2002; Liang et al, 2005). It has become ubiquitous today, but with mixed results. The slide shows help to provide strong graphical impact as "one picture worth a thousand words". However, the interactions and feedbacks from the students are still greatly limited. Sometime, the situation is even worse when the light is dimmed to improve

Recently, a small gadget called Clicker, or the first generation CRS, is gaining momentum among teachers throughout the K-12 and higher education, and to anywhere with a group of audience (Nicol et al, 2003; Siau et al, 2006). A clicker is a remote-like device that comes with a number of buttons and a wireless transmitter. After the instructor giving out a multichoice or true/false question, the students punch the buttons on their Clickers to select their

many applications. If used, they can greatly improve the user experiences.

of the corresponding cursor or object in the program.

Response System (CRS).

the visual contrast.

**5.1 Need of the next generation CRS** 

options (Patten, 2006; Richard et al, 2007; Roschelle, 2003).

answers. The answers then are instantly transmitted to the host computer operated by the teacher. A program will collect and summarize the answers and present the aggregated result to the teacher using a chart or graphic.

Both teachers and students welcomed the use of CRS. The engagement is bi-directional. The teacher can continuously assess the level of student understanding or mis-understanding. They can then give targeted clarifications or adjust the course material or pace to address the problems arisen. At the same time, the students can quickly apply the knowledge they just learned and answer the questions without raising hands, which can be intimidating to many. Since the answers are transmitted anonymously, the students will be free from the fear of peer pressure and public embarrassment.

However, still more features are desired for the Clickers. One major drawback of the current Clickers is its dependence on multi-choice or true/false questions (Siau et al, 2006). The teachers make up generally three or four possible wrong answers and mix them with the right one. As a legacy from the early computer-based standardized test, it is easy to grade. However, multi-choice or true/false questions are not the best or the only assessing tools. The number of choices is limited; the result can be skewed by test-taking techniques; and the teachers cannot directly know what the mistakes the students make from the answers.

Meanwhile, since the students can only choose from a limited list of options, their creativities are often ignored or discouraged. In any subject, there are always multiple solutions to a question, especially an open-ended question. In Science, Technology, Engineering, Art & Mathematics (STEAM) and many other fields, we often encourage students to focus on problem-solving progress instead of the final answer. Unfortunately, the multi-choice questions provide no room for the students to derive their own answers. It would be great if we can have a better tool that will encourage open-ended questions and promote problem-solving skills.

One attempt of improvement over clicker is to use touch sensitive tablets (Berque et al, 2004) or touch screen tablets. A touch sensitive tablet digitizes the strokes of the stylus on its surface and send the data stream to the host computer. However, due to the seperation of writing and displaying, the use of this kind device is unnatural and did not gain wide acceptance in the classrooms.

The touch screen pads include Tablet PCs (Koile & Singer, 2006; Willis & Miertschin, 2004; Zurn & Frolik, 2004) or iPad and its competitors (we denote them as xPads). A user can write on the touch screen of the tablet with a stylus or a finger. Then the hardware and software will convert the writing to either the text or graphics, and then display them back on the screen. Once networked together, tablets can be a great tool for a teacher to get instant feedback from the students. The feedback will not be limited to multiple choices, but on every part of the knowledge assessment that can be conducted with a regular paper test.

However, there are still several major drawbacks of these touch screen tablets. First is its cost. For example, the price of a tablet PC starts from \$1k and costs much more with rugged design. xPads are generally more affordable, but still costs hundred dollars each. The prices can easily rule out most classroom use, especially when they are under the stress of young students at their active years. Second is the different platforms of the tablet devices in the market. It is able to recommend but difficult to require all the students using the same

Optical Touch Screen and Its Application as a Next Generation Classroom Response System 129

As seen in Figure 8, we divide all the Z-Writers in a classroom to groups of 6. One of them equips a sub-server with an enhanced antenna. It acts as both a receiver and a relay. It collects the data from the group and relay them to the Bluetooth master in the host computer. In this network, each computer can handle up to 7 groups or 42 Z-Writers. That is enough for most classes and more than the maximum capacity that a teacher can handle at the individual level without a teaching assistant. For the larger classes with the help of teaching assistants, a local network of multiple computers or an outright change to using

The host computer on the teacher's side collects all the data from the sub-servers and save them into a database. A preview program converts the data into pixel points and display them in a preview window like the left part of Figure 9. With a quick glance, the teachers can have an instant view of how the students are performing. When the teachers need to annotate an individual student's work, they can select and magnify the one of interest and

 Fig. 9. Display in teacher's computer screen. Left: Real-time preview with all inputs. Right:

display it as seen in the right half of Figure 9 for in-class review and analysis.

802.11 can be employed. However, these are beyond the topic of this discussion.

Fig. 8. Set up of a Classroom Response System.

Magnified view of individual answers.

operating system in one classroom unless they are provided for free. Third is the distraction of the other software, especially the communication and entertainment software installed in the tablets. When a student is having an electronic device in hand, it is not easy to resist the temptation of returning a quick text message or playing a small game while the teacher is not around.
