If you're devoted to explosions, and who isn't, you'll love the new expanded 2nd edition of William Gurstelle's Backyard Ballistics, now 25% longer, with 25% more ka-boomery. Still the go-to reference work for building rockets, cannons (carbide and potato), flingers, fire kites, electromagnetic pipe guns, tennis ball mortars, cleaner-bag balloons, ballistic pendula and petards. You simply can't have more fun with common household materials. The soft-cover, 210pp compendium includes detailed and illustrated instructions, parts lists and sensible ways not to be hoist on your own petard. Be careful out there.

Start them out right with this (profusely) hand-illustrated, 96-page book: The Story of Inventions. Includes toasters, toilets, television, computers, cars, chocolate bars, dishwashers, pianos, flying machines, bicycles and blue jeans among many others. Includes a timeline, glossary and index. No age recommendations, but we like it for pretty much anyone.

But wooden gearheads only. Making Wooden Gear Clocks is a 64-page book complete with full-size patterns for making (6) operating mechanical clocks plus a gear-machine kinetic sculpture. From Woodworking & Crafts magazine, this is for fairly advanced woodworkers, and calls for having most standard tools plus a drill press, scroll saw, router and in some cases a lathe. The resulting clocks are both intricate and stunning.

50 Science Things to Make and Do is just that, a passel of experiments, all illustratively explained in two facing pages of this big 104-page flip book, and all easily done with common household items. Includes wind and water power, bugs, crystals, paper planes, rubber-band guitars, balances, gloop, optics and a ton of other fun, informative stuff. Officially classified as "cool" by several of our geekiest staffers.

Learn atomic weights while winning money from your classmates. Here’s a double deck of (104) cards plus (4) jokers all stored in a stylish box because no one wants to lose their gold, krypton or rubidium. In addition to the standard playing card values, the decks cover the periodic table of elements. Each card includes one element’s atomic number, symbol, series, melting and boiling points, period/group, uses, est. atomic weight, standard state, and the element’s name in English. Includes instructions for (2) educational games if you aren’t in the mood for canasta or two games of hearts. Up to date 6th Edition for all your fraction of a second elements.

Coding for Beginners…using Scratch is a 96-page, hardback, spiral-bound book for teaching kids with basic computer skills how to write code using Scratch, an educational programming language developed by MIT. (Has over 12 million registered users and 15 million shared projects.) Book includes art and sonic projects plus (4) games.

If they saw this color map eight times a day, they'd know where every place is-and its capital. Snap this tough, 8.5" x 11" laminated sheet into a school notebook and eventually they'll have to read it. It's a very nice world map with capital cities on one side, a U.S. map with state capitals on the other. It includes other major cities plus partial Canadian and Mexican bonus areas. Current, barring a coup since we got our latest shipment.

This 96pp, full-color, heavily illustrated book, "The Usborne Internet-Linked Book of Astronomy & Space," is written with a quick-link to the publisher's website, where there are updated links to internet sites that correspond to specific pages of the text. Sections include the solar system, stars, constellations, telescopes, photography and a plethora of astronomical facts and lists. From Usborne Publishing.

Our grandmother used to tell us that all the time, and we might have learned something while we were out there if she’d given us The Kid’s Guide to Exploring Nature, this 120-page paperback from the Brooklyn Botanic Garden. Chock full of information, photos and illustrations for exploring nature in both the city (includes pigeon info!) and the countryside, and in all four seasons. They might stay out of your hair until supper.

And find your way back with Map Reading and Land Navigation, a 113-page field manual. Originally published in 1993 by the Department of the Army, this reprint is a light and portable paperback.