A great way to create a science fair project about text messaging is to illustrate its cognitive effects on an individual using the technology. Have a participant answer simple questions, such as what is the last letter of your last name, what is your Mother's name, and in what town where you born. First administer the questions while the participant is not texting, and then administer those same questions again, in a different order, while they are typing out a text message. Use a stop-watch to compare the delay from question to answer in each case. Discuss how this would apply to the split-second decision-making ability required for safe driving.
Science fair projects about text messaging do not have to portray the technology in a negative light. Conduct a science experiment wherein two participants are each required to convey a message to another participant. Have the first message sender do so via traditional telephone call. Have the second convey that same message via text message. Time each experiment and repeat the experiments to get an average time for each. Which is faster? Discuss how much time would be saved or lost over a longer time-span, for example one hundred messages.
Survey cross-sections of various age groups. Start with other 3rd graders, and move up to high schoolers, college students, and adults. Finally talk to grandparents. Ask participants how many text messages they believe they have sent in the last week, month, and lifetime. Chart the results and make some observations, will this chart always look this way? Make some predictions based on the trend.
An interesting, albeit somewhat advanced, experiment would be to examine what requires more of a signal to receive, a text message or a phone call. You will need an external headset and a small wooden box. Make a hole in the box so the headset can be fed out. Cover one side of the box in aluminum foil and have a text and a call sent to the phone. If both are received without any difficulty, cover another side of the box and try again. Continue until one or both does not function. If possible test with multiple phones and establish a trend.