This non-randomized cluster-controlled trial examines the effectiveness of the digitalized and updated version of the It´s Up To You - program, a universal school-based prevention intervention for drug initiation and use targeting youth aged between 12 and 17 years.

The goal of this non-randomized cluster-controlled trial targeting youth aged between 12 and 17 years is to examine whether the updated and digitalized version of the preventive intervention named "It´s Up To You" program is effective in preventing drug use initiation and reducing drug use.

Participants in the experimental group will receive 6 sessions conducted by trained teachers. Each session will target a program module about the following topics: (1) What about drugs? (2) A way to start (3) Ana has fun (4) What do you connect to (about the use of the internet and social networks)? (5) Two versions of the same story, and (6) How do my parents come in?

Researchers will compare the experimental group receiving the "It´s Up To You" program to a control group receiving the usual teaching activities regarding substance use prevention. The main goal is to see if participants in the experimental group report lower substance (alcohol, tobacco, and cannabis) use and initiation after the intervention and at a 3-month follow-up related to the control group.

Inclusion Criteria:

• Schools having secondary education
• Schools located in Spain.
• Schools willing to participate under the conditions of the study

Exclusion Criteria:

• Schools applying the original "It´s Up To You" prevention program