Oddly enough, practice is, again, the central ingredient to learning how fractions work. Most kids love to be actively involved in the kitchen, and it is one of the best resource centers for applying fraction skills. Explain to your child that cooking requires an understanding of fractions. Then, you can have your child convert the ratios to fractions. For further practice, take a few recipes and ask them to re-write the amount of each ingredient to double the recipe.
Extensions can include re-writing for half as much, and so on.
Measuring spoons and cups are excellent hands-on tools for examining how fractions work. Give a wide variety of measuring utensils to your child and allow them to explore with dry ingredients, and again with water. This will reinforce the idea that, like whole numbers, adding and subtracting with fractions is absolute. Other areas of daily living that can reinforce fraction concepts include sewing and woodworking skills. With sewing, patterns and measuring tapes are excellent tools for working with fractions, and it reinforces how precise measurements must be in order to complete the project accurately.