Kids watch as Jason Cawrse operates a model of a canal-lock system at last year’s Engineering Family Day at the National Building Museum. (Astrid Riecken/For The Washington Post)

You probably enjoy making things — plastic block fortresses, rubber band bracelets, paper airplanes, to name just a few kid favorites.

But if someone suggested that you play engineer for a day, you might wonder how that could be fun. If that’s your reaction, you haven’t been to Engineering Family Day at the National Building Museum.

Last year’s event included making vehicles — foam-plate aircraft and foil boats — and then testing them. Kids could construct a virtual bridge and run a simulation to see whether the bridge would support vehicles. Others built Lego buildings and tested whether they would remain standing if struck by a tsunami, or giant wave. A very popular booth explained the science of popcorn — with samples!

It was all about learning by doing.

Many of the people running the experiments were engineers. So kids could ask questions about different kinds of engineering: computer, mechanical, electrical, aeronautical and many others.

This year’s Family Day, which is Saturday, will feature slime-making, catapulting a table tennis ball, controlling a robot and many other engineering-related activities to keep your hands and your mind busy.

What: Engineering Family Day

Where: National Building Museum, 401 F Street NW. Metro’s Judiciary Square station is across the street.

When: Saturday, February 22, 10 a.m. to 4:30 p.m.

How old: Best for ages 6 to 12.

How much: Free. Donation suggested.

For more information: A parent can call 202-272-2448 or visit