Paste not only helps things stick together, but it also makes a great science project. Investigatory projects on paste lend themselves to things such as making and testing pastes, testing the strength of paste and learning how to make it dry quicker. Protect your work area with a covering to limit damage from accidental spills.
Combine 1 cup flour and enough cold water to make a cream-like consistency in a saucepan. Heat the mixture to a simmer, for about five minutes, until the mixture gets thick. Pour the mixture in a container and allow it to cool. Add food coloring to the paste if desired. This type of paste is more like traditional school glue.
Make another batch of paste that is for projects like papier-mache. Combine ¼ cup flour with 1 cup water in a saucepan; the mixture will look runny. Bring the mixture to boil for two to three minutes and allow it to cool slightly, then pour it in a container to continue cooling more.
Make a no-cook type of paste by combining water with 1 cup flour and two pinches of salt in a bowl until the mix is gooey, but not runny. Transfer the mixture into a container.
Compare the three different types of paste to see what works best connecting two things together. For example, try pasting foam pieces to construction paper, construction paper to construction paper, or joining newspaper strips such as for traditional papier-mache techniques. Report results such as what type of paste worked better on paper products, which dried fastest, which dried slowest and which was the most difficult to work with.
Strength of Paste
People normally use paste for bonding together lightweight material such as paper. Test the strength of paste by applying the paste to two pieces of paper while leaving a small gripping area. Wait a few minutes and then see if you can separate the papers. If the paste isn't completely dry, or it doesn't bond well, you'll be able to pull the papers apart easily. Stronger paste may rip the papers apart as you tug on them.
Observe Paste Drying
Watch how the paste dries, and see what you can do to make it dry quicker. For example, pour or squirt some paste onto your hand, rub it around and then hold your hand flat. Watch what happens to the paste as it dries on your hand, and observe how it dries. You'll likely see that the paste dries from the outside in, and dries quickest where there is less paste on your skin. Let the paste completely dry and then gently peel it off your hand to make it look like you are shedding skin.
Squirt a puddle of paste onto a piece of paper and watch how it dries. You'll likely see a type of "skin" form on the paste, so that it no longer looks wet, but if you poke it with your finger, you'll see how it's still wet inside.
The paste dries when the water evaporates from the mixture. Try to speed up the drying time of paste by blowing on the paste or putting it in a warmer place, such as a sunny window. Compare the wetness of the paste to a sample of similar size that wasn't blown on or set in the sunny place.