Dr Katz, professor of early childhood education at Illinois University, particularly criticised work involving teddy-bears and cutting out letters.
She complained to early-years specialists at a conference in London organised by the Royal Society of Arts that US nursery projects always had to be "exciting". Play was important, she said, but in the US children often did nothing else.
She had heard one little girl who was busy cutting out autumn leaves tell her friend: "Hey, you know what, this is really dumb but my mum will love it. " And on teddy-bear projects, Dr Katz said: "Sorry, but this is not worth children's time. Fun is a cheap goal. It's easy come, easy go."
Dr Katz, well-known for her hard-hitting early-years commentaries, also criticised the RSA's Start Right report, The Importance of Early Learning, which has been widely praised since it was published in the UK in March 1994.
She criticised the RSA's use of the term "purposeful play", which she called a contradication in terms. She asked why childen had to be "independent learners" at three or four - interdependent learners, collaborators and co-operators, yes, but not independent learners.
Dr Katz was also scathing about the RSA's call for the systematic education of parents on rearing their children, asking who would decide what is good parenting in a multicultural society.
The RSA named six types of early learning, but had not emphasised the "development of dispositions," said Dr Katz. She defined "dispositions" as habits of mind such as curiosity or being a reader as opposed to learning reading skills.
Dispositions could not be taught; they were picked up from people who had them or made them visible in some sense.
The intellectual - not the academic - development of young children was crucial, she argued. The most important dispositions were inborn and the teacher's task was to strengthen them. If they were damaged by inappropriate experience, they were extremely difficult to recapture.
Sir Christopher Ball, author of the report, said afterwards that her comments were the most serious critique of Start Right yet.
The conference also heard from another eminent speaker from overseas, Dr Anne Meade, director of the New Zealand Council for Educational Research.
Dr Meade described the successful 1985 campaign in her country to gather together kindergartens, play centres, child-care centres, Montessori centres - in fact all the services for the under-fives - and call them "early childhood services".
The administration was switched from social welfare to education, they were all given government grants and fee subsidies for families were promoted.
Although the present Conservative government in New Zealand was now attempting to dismantle what Dr Meade called a "stunning change," she stressed the importance of "shaping the discourse". The words "pre-school" and "child care" had almost disappeared in favour of "early childhood centre" and "early childhood service".
All workers with young children were called "early childhood teachers", and people like herself with primary qualifications were asked to upgrade to an early childhood education qualification. The change in terminology was intended to change people's thinking, she said.
Professor Philip Gammage, dean of the faculty of education at Nottingham University and another conference speaker, criticised the struggles between the teachers' unions and the tensions among early-years' groups that had prevented the lobby for young children's education from speaking to the Government with one voice.
He criticised the teachers' unions for not sending a single representative to such an important early-years conference. Early years, he said, was always at the bottom of their agendas.
Professor Gammage said: "I have come to the point in my career when I want to be intensely political. Children in this country deserve better. I don't want to see the absolute inability of the system to provide for the changed family and changed needs. I no longer have the patience to wait."
Some conference delegates were depressed about the Government's refusal to listen to what they and parents wanted. But Sir Christopher Ball said it would be the early-years' lobby's failure if it did not mobilise itself before the next general election. All three political parties were interested - and ignorant - about young children.