Baroness Blatch, Minister of State for Education, also confirmed that the reading comprehension tests used voluntarily by some teachers this year will be compulsory for all schools next summer.
Pupils in their second year of primary school will be expected to answer simple algebra questions and physics problems.
The algebra will be basic: filling in the space in a sum such as 3 + ? = 10, using piles of counters, or seeing patterns in numbers, for example. Physics tests for children of average ability might include showing how magnets can be used to sort objects, or using thermometers to find temperatures of liquids; brighter children might make an electric circuit including lights and buzzers.
The spelling test will be 'short and rigorous', Lady Blatch said. Her officials added that sample tests have yet to be drawn up by the Schools Examination and Assessment Authority. But the test will probably comprise a list of 20 to 25 words, starting with easier, single-syllable words, increasing in difficulty to oddly spelt and multi- syllable words.
The test will only be given to children who have shown in the reading tests that they are average or better than average ability - in other words, those who attain national curriculum level 2, 3 or 4. The one in four children who are still not reading fluently will not be expected to sit the test.
At present, reading tests simply find out whether a child can work out a written word and say it out loud correctly. Teachers test the children by reading specific passages of set books, ticking off highlighted words according to whether the child reads them correctly, stumbles, or needs prompting. The comprehension test goes further, asking the child to answer a short written paper on the meaning of the passage which has just been read with the teacher.
Lady Blatch insisted that the 50 items in next year's national curriculum tests for seven-year-olds would be manageable.