26 Problemas resueltos de navegación astronómica para capitanes de yate

Internet security breaches have been in the news of late. Organizations, governments, businesses, and individual internet users are all at risk. This book introduces readers to the importance of cybersecurity and addresses the current risks from hackers, viruses and other malware, identity thieves, and other online perils. It provides concrete measures that young digital natives can take to protect themselves and their computers, smartphones, and other devices. This volume's lively, cautionary narrative and useful tips will help readers effectively defend their identities and data.

Tommy Fuller and his family help a runaway slave family follow the stars in the Little Bear constellation to freedom.

José Martí was barely 16 years old when he began to fight for the independence of his homeland through his writing. At 17 he was declared an enemy of Spain and sentenced to six years of prison and hard labor. But that did not stop him. Martí dedicated his life to defending Cuba's right to independence. Today he is remembered and honored as a man of integrity--brilliant and courageous--and as a lover of freedom and peace.

Si tienes un alto sentido de la justicia, mucho sentido del humor y un gran corazón, este libro es para ti. ¡No eres nunca demasiado joven para cambiar el mundo! ¿Te sumas? En esta guía práctica te damos pistas para hacerlo: consejos y tácticas para marcar la diferencia, un montón de actividades paso a paso e historias inspiradoras de niños y niñas que han abierto camino, desde activistas como Malala Yousafzai o Greta Thunberg hasta jóvenes que, como pronto harás tú, han conseguido que se escuche su voz y cambiar las cosas.