Before choosing a science fair topic -- and buying supplies for it -- sit down with your child to review the school's rules and timeline. Discussing the parameters of a project beforehand will also help you determine whether an idea can be tested in a certain period of time and on budget.
With a practical mind-set, you and young Einstein can narrow the project's focus enough to prevent mix-ups along the way. Say your junior scientist wants to plant vegetable seedlings outside during the coldest month of winter. It's not feasible to conduct experiments unless you live in warm enough temperatures to dig into the ground. Instead, wait until the weather is warmer or pursue something else to avoid buying indoor heat lamps and other expensive supplies. You want to have nature and time on your side.
Thinking practically may also include framing projects around holidays. One middle school science fair project tested the rate at which Christmas tree needles fell off when dressed with different decorative lights [source: Glidden]. The experiment was practical: The student worked with a tree business to take unwanted treetops left over from the holidays. Her experiment suggested that one type of lights caused fewer needles to fall and even emitted less heat.
When it comes to buying supplies, keeping costs down may be as simple as using a calendar. Click to the next page to find out more.