Having seen the writing on the wall for the CSF Bill, the government fired up a plan B, in the form of a consultation into what constitutes a suitable education. There is currently no definition in law, but courts have indicated that education is deemed to be “efficient” if it achieves what it sets out to achieve and “suitable” if it “equips a child for life within the community of which he is a member, rather than the way of life of the country as a whole, so long as it does not foreclose the child’s options in later years to adopt some other form of life if he wishes to do so.”
I suspect that there is no good universal definition of "efficient", so the one that the judge used is likely to stick around. School is certainly not efficient when looked at on the basis of an individual child, who is likely to spend much of the time in class not being educated. So the government may need to tread carefully lest they come up with a definition that shows up their system in a bad light. It can be argued that they fail even this loose definition because school sets out to provide each child with five GCSE passes including English and Maths and most definitely does not achieve that. So, planks and splinters, perhaps the state needs to get its own house in order first.
This leaves us with "suitable". Once again, for school this can probably be expressed in terms of government targets, because that is how they think. Five GCSEs at A-C and half of children going on to university where they can build up huge debts while gaining devalued or worthless degrees.
However, many home educators reject those targets, or at least prefer to place them in a wider context. The government position is simple: it considers academic achievement to be the only metric, forever stressing how many children have achieved their targets. Home educators tend to be more focused on the overall quality of life, which is much harder to assess and is definitely not amenable to a simple tick-box approach. The government introduced its Every Child Matters programme, but this seems to be a bit of an afterthought, and certainly doesn't appear to apply much in some schools. It is very much a product of the nanny state, trying to remove common sense and replace it with a set of rules. "You will enjoy yourselves and you will do it like this."
Anyway, back to "suitable". This is a very individual metric. Bill Gates decided that he didn't need a university degree, and given his career, one can argue with him. Alan Sugar and Richard Branson gained much of their education in the school of life and have been very successful. Yes, these are three extreme examples, but they are part of a spectrum of people who succeeded with a wide range of educational achievements at 16. Looking the other way, there are doubtless people with good university degrees who are unsuccessful, and more who achieved the magic five GCSEs. For whatever reason, academic achievement failed to equip them for their situation.
This is where home education scores more highly, because by the nature of it, children are expose to the world and are actively encouraged to pursue their ideas, often to the short-term exclusion of all else. Here's another term: "balanced curriculum". This is a very misleading thing, which the government defines as advancing equally in all subjects each year. Why does this have to happen for an education to be suitable? In the limit, a child could learn one subject per year with a GCSE at the end for eleven years and come out at the end of compulsory school with eleven passes. However, a snapshot at age eight would see that child as lacking in certain areas despite the three or four exam passes. In practice there has to be overlap between subjects because basics such as maths and English will find their way into other areas of life and no one subject is an island, so it is inevitable that advancement is required along a broad front.
To follow this overlap thread a bit further, ask why we have to have arbitrary boundaries of subjects? The sciences are all inter-related, and maths features in all of them. A child studying chemistry will be exposed to aspects of physics and biology and will use maths as a tool. An interest in volcanoes can be expanded to include history - dealing with effects of volcanic action, geography - pinpointing locations of volcanic activity, geology - discovering rock types and plate tectonics, and more. Astronomy can be handled in a similar manner, plenty of rich history with religion and the centre of the universe, a bit of maths and physics to explain the motion of bodies, etc.
So what is "suitable"? To go back to that judicial definition, it pretty much hits the spot. A child who has, by adulthood, mastered enough skills to see him through the next stages of his life, but is also equipped to learn new ones as the need arises, meets that definition perfectly. For each child the skill set will be different according to interests and upbringing, but that is because we are not cookie-cutter clones to be assessed with a standard set of tick boxes.