play dough recipe,and if you add dry koolaid instead of food coloring, you have smell-o-riffic dough! cup of salt instead. and I did add the glitter for fairy play dough.) I don't know what the cup of salt instead" is for but I'm gonna try this
Colored water in squeeze bottles for drawing in the snow. Totally doing this this winter. Science and Art grade Teach a lesson on the weather changes outside. Then take the kids outside and paint the snow with these colored water bottles
25 Awesome Projects for Tween and Teen Boys (Ages 10 and Up)
Marble Races with a cheap pool noodle (occupies the kids for hours.) Did this, but instead of cutting the pool noodle, the marble is small enough to fit inside the full noodle to roll down. Then can use the noodle for other things too!
DIY easy bubble blower - made with empty water bottle! The kids loved it! There was a "fight" over a larger water bottle until the kids discovered you can make longer bubble "tails" with a smaller bottle (requires less air to blow).