Real bridges are not repeatedly built, then loaded until they collapse, and then rebuilt, until they can support the required load. An associate shared with one class, drawings of a spacecraft he'd made in grade school. As a aerospace engineer, he's now doing what he dreamed of as a child. It is a great spark for discussion. The children enjoyed the hands-on experience with the rugged toy.
Many times there are simple inexpensive substitutes for costly, complicated and fragile models.
Toys are a safe bet with grades K through 3. Here's a new take on an old idea. Now you can assist students with researching this information in a number of ways. Some states have a website or make their e-mail addresses accessible for information inquiries. Children may also be shown the formal and traditional forms of business letters to request this information and be shown how to them through the U.S. Postal Service.