It means getting into the various parts of the seder in more depth, and providing some understanding of the meanings. The Ten Plagues seems to inspire many creative activities. Keep the following items in a separate basket for each plague, ready for a child to distribute to seder guests. Add red food coloring to the water pitcher on the table. Collect lots of plastic frogs of all sizes, colors in a basket.
Some people throw rice instead.
Collect frightening plastic animals and small toys. This is a cattle disease. Collect plastic cows, have the kids apply bandages and distribute them. Give guests bandaids to stick on interesting places on their bodies. Children with a theatrical bent enjoy this one.