Going to a birthday party is always a blast, especially when there are fun games to play! Cam Jansen and her friend Eric are having a great time celebrating with their classmates. The best part of the party is a special guessing game featuring a giant glass jar packed to the brim with tiny toy dinosaurs. Whoever guesses the exact number of dinosaurs gets to take the whole jar home! But right after a wild game of musical chairs, the host realizes someone has secretly opened the jar and changed the number of toys inside. The only clue left behind is a suspicious smudge of chocolate cake. Luckily, Cam has her amazing photographic memory ready to go. With a quick Click! she can remember exactly who was standing near the prize table. Can Cam put the clues together and solve this sweet birthday puzzle before the party is over?