Bell's Breakthrough

When Abigail, Jacob, Zack, and Bo travel back in time, they discover Alexander Graham Bell has given up on his telephone and is ready to quit. The friends must persuade the stubborn inventor to keep trying, using their knowledge and enthusiasm to push him back toward invention. As they navigate historical obstacles, they learn about perseverance and the impact of encouragement. This adventure is the third book in a series that blends history, science, and friendship.