Business leaders have warned pupils may be turned off science by the "sheer scale of prescription" in the new curriculum.
According to the CBI the new system will leave pupils little time to do practical experiments, but young people will only develop a serious interest in science if they have the chance to get hands-on experience in the subject.
It also raised concerns about new proposals for design and technology (D&T) lessons, suggesting that the plans "lack academic or technical rigour" and are "out of step with the needs of a modern economy".
The CBI's comments come on the day a consultation into the government's new draft national curriculum is due to close.
In its submission to the consultation, the group says that businesses share the government's view that there is a pressing need to raise the performance of the school's system, and that mastering English and maths is central to education.
But it adds that it has particular concerns over science and D&T and suggests that more needs to be done to make sure that these subjects "inspire and excite young people".
"The future prosperity of our economy depends on inspiring and exciting young people about potential careers in science and technology in far greater numbers than in the past," the CBI's submission says.
"Encouraging young people to develop a serious interest in science depends above all on their having plenty of opportunity to get hands-on experience of conducting practical experiments.
"Achieving that in turn requires science teachers to have flexibility to innovate in how they develop young people's scientific understanding. The scale of detailed prescription on programme content for science in particular runs the risk of hindering creative delivery."
Neil Carberry, the CBI's director of employment and skills, said: "We're concerned that the sheer scale of prescription risks hindering teachers' creativity, flexibility and innovation in the classroom.
"Business demand for science, maths and technology skills has long outstripped supply. It risks squeezing out space for practical, hands-on experiments, which are vital to help children develop an interest in science from the start of school."
He added: "The proposed D&T curriculum is out of step with the needs of a modern economy. It lacks academic and technical rigour, as well as clear links to the realities of the workplace.
"The proposals focus on basic craft skills at the expense of high quality learning, which risks reinforcing existing prejudices about applied subjects being second-rate."
The Institution of Engineering and Technology (IET) also warned that the proposed changes to the D&T curriculum lack the ambition needed to foster a future generation of engineers and technicians, in its submission to the consultation.
The IET says the changes appear to set significantly lower expectations for pupils, with an inappropriately high focus on practical and life skills at the expense of encouraging students to innovate, design, create, and build, which it says should be at the heart of the subject.
Paul Davies, IET head of Policy, said: “The draft D&T curriculum has lacked expert input, and as a result, does not provide the rigour and challenge consistent with the needs of today.
“We are concerned about the lack of emphasis of how D&T relates to and is used in the creation of new technologies and modern manufacturing processes, which is very important to inspire students into strategically important related subjects such as engineering.
“Without this link, students will not be adequately prepared for career opportunities and the needs of employers and, more worryingly, this will exacerbate the technical skills shortage that the UK is currently facing.
“This is contradictory to the government’s attempts to rebalance the economy towards manufacturing industries.”
Ministers set out their new back-to basics curriculum for England's schools earlier this year.
The new curriculum, due to be introduced next year, contains plans for youngsters to be taught fractions, grammar and how to recite poetry from an early age.
It also outlines proposals for pupils to be taught a chronological history of Britain, to begin to write simple computer programs at age five and to learn the names of continents, oceans, countries and geographic features as well as how to use maps and compasses in geography lessons.