45min: Students are following a lesson dedicated to the subject “Preparative treatments in fruit and vegetable processing” in the context of quality controls in the initial product. While analysing how and why these are applied, the factors and possible effects to the last product, the development of the learning scenario will start by using an initial google form survey so as to identify possible cognitive gaps. Students are called to work as teachers independently as possible based on a webquest of three steps: In the first step students attend an interactive presentation -created by using genially, and with the use of some mentis -created by using mentimeter-, where will be used our real-life questions such as stated before we will start -according to the answers of the students during the brainstorming, and guiding the discussion in relation to preparatory operation on receipt of the product to the industry- to state our topic. In this presentation will also be a self-evaluation quiz. In the second step is given an article and some resources so as to find, analyse, and synthesize information on our topic. In the third step students are called to create a poster on preparatory operations during fruit and vegetable processing. Then their posters are presented and discussed.

45min: Students will be prepared for what they must do in the following lessons in different STEM and non-STEM lessons according to our learning scenario, emphasizing to the use of automatic machines, in order to to develop how imaging technology and automated food sorting processing machines work and how these could ensure faster and in a low-cost the safety and quality of our food, reducing food waste. There will also be a brief presentation so as to be better prepared for the engineering lesson. They will also be informed on the way that their work will be evaluated and we’ll create together the rubric.

90min: Briefly repeat the terms of qualitative and quantitative control of delivered vegetables and fruits, and students are asked to brainstorm on quality measurements, the major causes of deterioration, the reliable methods for evaluating the quality and quantity at the reception, and mandatory processing operations and practices. After that, students are divided in two groups: the worksheets are given, explained, and discussed. Students take place on the same observations: a) effect of dehydration temperature on the quality characteristics of the dehydrated apples and b)effect of blanching on the quality of dehydrated vegetables BUT those are dehydrated in different temperatures.  Students are presenting their observations, and their meaning for the quality of their product, and the way that treatments applied at the preparatory processing treatments affected the product.

180min: Briefly repeat with the students the terms standard solutions, quantitative concentration, significance and connection of analytical chemistry with quality control of fruits and vegetables, gravimetric and volumetric methods used in the fruit and vegetable industry. After that, interpret the procedure of work in the laboratory exercise Determining the acidity and vitamin C. The students will be divided into groups of two students. Each group will determine the acidity of a different fruit juice. To determine the acidity will use a method based on titration with sodium hydroxide solution in the presence of phenolphthalein indicators. Two analyzes are performed. Students write a report on Determining Fruit Acidity and sort out the results. After that, in the final part of the class, students will compare and discuss the obtained results for different types of fruit juices.

180min: Students watch an interactive video, and answer the questions that it includes. They write their ideas and suggestions in a padlet for the construction and operation of the sorting machine that they will build. The teacher appoints three students "engineers" three “electricians” and three "programmers", depending on the content of their posts on the padlet. Students are divided into four groups so that each group has an "engineer", an “electrician” and a "programmer".  Group A: Undertakes to build the chute. Group B: Undertakes to build the gyro sensor, the color squares and the tracks. Group C: Undertakes to to build the color sensor 1, the color sensor 2, the touch sensor and the turntable. Students in their groups decide which pieces of sensors and machines they need and record them. Then they build the parts of the machine assigned to them. The three "engineers" work together to connect the individual parts of the machine. The "programmers" with the help of their team members discuss and decide with which software they will do the programming. The "programmers" with the help of their team members and the software they have chosen make the programming so that the machine sorts the pieces in the containers according to their color. Meanwhile, the three "electricians" work together to connect the cables to the machine. The "programmers" test their codes on the machine. The best is chosen. The machine is started and any errors are corrected. There is a discussion about the problems encountered and possible improvements. Each student scores the teams on a scoreboard.