There's a lot of neat books out there with science experiments for kids to do at home. I love Science Wizardry for Kids by Margaret Kenda and Phyllis S. Williams.

Here's an example of some of the material:
"Every good chemist needs to know the difference between an acid and a base.
Besides their importance in chemistry acids and bases are necessary for cooking. The right sort of acids add flavor to food. They give food a tangy (or sometimes a sour) taste. Also, acids can help preserve food.
Bases can combine with acids to help with baking. The chemical reactin makes biscuits and cakes rise.
The strongest acids and bases, though, are not foods. Just touching a really strong acid or base can cause a bad burn......etc
Here's what you need
A red cabbage
A grater
A stainless steel pan
Water
A strainer
A glass jar
A label

Here's what you do:
1. Grate the cabbage into the stainless steel [sauce] pan. You should get an adult to help you with the grating.
2. Pour in water until you just barely cover the cabbage.
3. Boil the cabbage until it's tender. Before the cabbage is done, it will have lost some of its red color and will look a little bluish. The water will have a color between blue and red.
4. Carefully strain the water into the glass jar. Again, you'll probably want some adult help.
5. Label the jar: INDICATOR. You can use your indicator now, or refrigerate it for later.
6. Don't throw away the cabbage. First, add a little vinegar to turn the cabbage back to a more appetizing red color. Then add a little butter, salt and sugar. If you wish, stir in chopped apple and a few raisins.

Note: When you add vinegar to the cooked cabbage, you add an acid. That makes the cabbage turn form bluish to bright red."

How to use the indicator
Get small jar or plastic containers.
A piece of paper, paper towel. or paper place mat for each container.
A medicine dropper or drinking straw

Put a little of the things you want to test in the little container put some of the indicator in (using eye dropper or drinking straw--suck some up [don't drink} cover the end of the straw with your finger and transfer to container).
"You'll see a color change" the cabbage-water indicator turns an acid red, a base blue"

Things to test apple juice, mashed banana, coffee, cola drinks milk, sugar, pickle juice, tomato juice, toothpaste, vinegar and you can think or many more things...we tested just about anything we could get into a container.

You can also use tumeric as an indicator..another title "Mix Up An Emelusion (And Make Salad Dressing)
with recipe and "Mix Up A Colloidal Mixture (And Make A Gelatin Dessert) also with a recipe...."Create Edible Glass" with recipe that produces the kind of sugar glass they use in the movies to crack over someone's head......"Make Your Own Old-Fashioned Milk Paint" with a recipe "Hold A Floating Contest With Fruits and Vegetables".....
This is getting long I'll try to E-mail you more.