While most elementary school teachers have had some science courses in college, these tend not to be in fields like physics, engineering, and chemistry. Studies have shown that most teachers at this level do not feel confident in their ability to teach these subject areas to their students. It's hard to teach what you don't know well.
Many teacher training programs have responded to this situation by ramping up the coursework and training required of future teachers. And schools across the country have sought ways to expand their STEM education in early grades.
One tool that both teacher training programs and elementary and middle schools are using effectively is the Next Generation Science Standards (NGSS). These standards have been adopted in 19 states and the District of Columbia and another 19 states have adopted similar new science standards, according to the National Science Teachers Association. There is an extensive website dedicated to the NGSS, as well as several long videos. But, for a short but helpful video that explains the NGSS and how they work, you might want to check out the link below: