This author's mission was to try out some materials being developed by a member of an advisory team, and give feedback about how they worked in the classroom. She was provided with detailed lesson plans, including mental and oral starters, and a list of resources. Her objective was to explore and interpret collected data using ICT in order to draw conclusions. Starting first with the recommended graphic calculators, she found that neither she nor the students had adequate skills to interpret the lessons. Determined to see her mission through, she chose to readjust the lesson plan and use Excel, with which she has much more experience and confidence and feels more comfortable using it in front of a class of pupils whose ICT skills are better than hers.