The number of primaries where teaching overall is good or better also fell this year.
The chief inspector's report highlighted a gap between achievement in core and foundation subjects. He said that teaching was worst in geography, RE and information and communication technology.
Mr Bell said schools had a "moral imperative" to provide children with a broad and balanced curriculum.
"We should want our young people to make things, to experience the finest music, to read a wide range of difficult books, to know how to conduct a fair experiment and to understand what constitutes a sound argument," he said.
It is the second year in a row that Mr Bell has called for improvements in primary schools.
Last year, he warned that pressure to improve English, maths and science was producing a "two-tier curriculum".
Since then, the proportion of primaries where teaching is no better than satisfactory has increased from a fifth to more than a quarter in 2003-4.
Although primaries welcomed the proposals in the Government's Excellence and Enjoyment paper to make the curriculum more creative, they have been cautious about implementing it, the report said.
Teaching is strongest for nursery-age children and in the last year of primary but weakest for six, eight and nine-year-olds.
Mr Bell said there was also too much variation in the quality of teaching across subjects.
An Ofsted report published in November identified geography as the worst taught subject in primaries. This week's report highlighted problems in ICT which, despite improvements, remains the subject where there is most underachievement.
Mr Bell praised efforts during the past decade to raise standards in English, maths and science, noting that improvements in results of 11-year-olds resumed last year after a hiatus lasting several years.
Despite the improvements, he said there was a "pressing need" to tackle literacy and numeracy for pupils in their first secondary year who had not reached the expected standard in primaries.
Mr Bell's call for a broad and balanced curriculum is music to the ears of staff and pupils at Westdene primary in Brighton.
Creative nursery classes see children looking for hidden number shapes in huge bowls of jelly, and practising scissor skills by cutting the grass. A highlight of this term will be a multicultural arts festival involving Bollywood dancers, African stone-carving and a samba band.
The 500-pupil school was praised last year for teachers' "infectious enthusiasm", inventive and engrossing lessons, high expectations and excellent out-of-lessons opportunities.
Max Bertrand, 11, said: "Our teacher hurt herself doing star jumps down the slope to the beach - she's that enthusiastic."
But being an excellent school is not all a bed of roses.
Ofsted's only criticisms concerned a lack of planning at the foundation stage and poor accommodation: a third of pupils are taught in temporary buildings. Headteacher Debbie Crossingham said: "If we had been put in special measures they would probably have done something about it (the buildings)."