This text is a compilation of step-by-step instructions for how to build nine different types of catapults and trebuchets. Each set of instructions includes dimensional drawings of all wooden parts, lists of required hardware and sources, an abundance of photos, diagrams, and detailed descriptions of the assembly process.

Whether playing at defending their own castle or simply chucking pumpkins over a fence, wannabe marauders and tinkerers will become fast acquainted with Ludgar, the War Wolf, Ill Neighbor, Cabulus, and the Wild Donkey—ancient artillery devices known commonly as catapults. Building these simple yet sophisticated machines introduces fundamentals of math and physics using levers, force, torsion, tension, and traction. Instructions and diagrams illustrate how to build seven authentic working model catapults, including an early Greek ballista, a Roman onager, and the apex of catapult technology, the English trebuchet. Additional projects include learning how to lash and make rope and how to construct and use a hand sling and a staff sling. The colorful history of siege warfare is explored through the stories of Alexander the Great and his battle of Tyre; Saladin, Richard the Lionheart, and the Third Crusade; pirate-turned-soldier John Crabbe and his ship-mounted catapults; and Edward I of England and his battle against the Scots at Stirling Castle.

Let children experience the learning power of play! Let’s Play is a handbook full of child-led, open-ended learning adventures. The 39 fresh, fun, and budget-friendly activities (plus more than 225 play variations) are packed with learning that helps children develop important motor, cognitive, language, and social skills. These activity starters were all tested by a slew of early childhood professionals and approved by the children they work with. Building on the early learning principles presented in the author team’s first book together, Let Them Play: An Early Learning (Un)Curriculum, they also support your transition to a play-based, child-led (un)curriculum. Jeff A. Johnson has more than twenty years of early childhood experience as a former child care center director and current family child care business owner. He is a popular keynote speaker, trainer, and author of six books. Denita Dinger has been a child care provider for more than ten years and is a frequent speaker at early childhood conferences, focusing on the topics of hands-on and play-based learning. This is her second book.

In its new pocket-size format with a rubber-band closure, Rubber Band Engineer: All-Ballistic Pocket Edition is a fun-filled book of backyard projects that's perfect for gifting. Shooting far, flying high, and delivering way more exciting results than expected are the goals of the gadgets in Rubber Band Engineer: All-Ballistic Pocket Edition. Discover unexpected ways to turn common materials into crafty contraptions that range from surprisingly simple to curiously complex. Through vivid color photos, you'll be guided to create slingshot rockets, unique catapults, improvised darts, and a clever crossbow. Whether you build one or all 10 of these designs, you'll feel like an ingenious engineer when you're through. Best of all, you don't need to be an experienced tinkerer to make any of the projects! All you need are household tools and materials, such as paper clips, pencils, paint stirrers, and ice pop sticks. Oh, and rubber bands. Lots of rubber bands. Grab your glue gun, pull out your pliers, track down your tape, and get started on the challenging, fun, and rewarding journey toward becoming a rubber band engineer.

A man’s home is his castle, or so the saying goes, but could it withstand an attack by Attila and the Huns, Ragnar and the Vikings, Alexander and the Greeks, Genghis Khan and the Mongols, or Tamerlane and the Tartars? Backyard Ballistics author William Gurstelle poses this fascinating question to modern-day garage warriors and shows them how to build an arsenal of ancient artillery and fortifications aimed at withstanding these invading hordes. Each chapter introduces a new bad actor in the history of warfare, details his conquests, and features weapons and fortifications to defend against him and his minions. Clear step-by-step instructions, diagrams, and photographs show how to build a dozen projects, including “Da Vinci’s Catapult,” “Carpini’s Crossbow,” a “Crusader-Proof Moat,” “Alexander’s Tortoise,” and the “Cheval-de-frise.” With a strong emphasis on safety, the book also gives tips on troubleshooting, explains the physics behind many of the projects, and shows where to buy the materials. By the time they’ve reached the last page, at-home defenders everywhere will have succeeded in creating a fully fortified home.

Ken and his EngiNerds crew return in another nutty and nerdy adventure as they face down an alien to save the planet! Alien invasion? At the end of Revenge of the EngiNerds an alien appeared, and it turns out he’s the real deal. He explains he was sent to Earth as an envoy to scope things out for a planned massive, futuristic billboard—which will mean demolishing the planet! Here? On Earth? In their town? Not if the EngiNerds have anything to say about it. Time to save the day and the planet!