Santillana gestiona sus contenidos a través de ecosistemas digitales donde se activan los libros mediante códigos que suelen venir en la contraportada de los libros físicos.
Wait, but the user wants a paper, so I need to present accurate information. I need to verify if Santillana does offer free digital resources in Costa Rica through their official channels. Maybe there's a specific program. Also, check Costa Rica's national education system's approach to digital education. For example, if the government partners with publishers to provide materials, that would be a legal avenue.
It looks like you're looking for free digital PDFs of Santillana textbooks for 7-year-olds (likely 1st or 2nd grade) in Costa Rica.