High Israeli birthrate (3.1 vs. 1.7 OECD average) sends our education and economy into a downward spiral
Higher birthrate means more children and less working-age adults in the population. The below flowchart shows the process of gradual deterioration of our education and economy caused by our excessive (vs. the OECD) birthrate:
Demographic trends specific to Israel aggravate and accelerate the above process
In other OECD countries, parents' income level hardly effects their fertility. In Israel, poor parents usually bear many more children (6~7) than affluent ones do (2~3), and this trend usually continues in next generations. As the result, rises the percentage of poor children in population. Statistically, they are worse learners than children of affluent parents are.
In Israel, relatively to other OCED nations, there are more families with more than average siblings. Statistically, the more siblings – the lower their cognitive and learning levels.
PROGNOSES (if Israel maintains its present fertility rates)
Today, average Israeli child (0-15 y/o) is provided by ~2 adults of working age (16-64), while average OECD child has 3.6 providers. As average Israeli adult's work productivity is only 75% of his OECD counterpart, the actual resources available to each Israeli child are only ~40% of those available to an average OECD child. But we manage to give our children relatively more (54% of average OECD in kindergarten, 85% in primary & secondary school) by reducing budgets for health, infrastructure, tertiary education, environment protection etc.
If each population sector keeps its present TFR, in 2035 the average TFR will be 3.5, in 2055 – 4.0. So, we'll have ever less providers per child, i.e. ever less money for educating our young.
Teachers' quality will decline: the more of them are needed (for ever growing children/adults ratio), the less money is available for each teacher's training and future wages. Better qualified candidates avoid joining the profession.
Being both poor and having more siblings predicts, statistically, that these children will be worse learners. Educational achievements (PISA exams for 15 y/o) will dwindle, as the ratio of poor children with many siblings will rise. Also, the achievement gaps between rich and poor children (today the highest in OECD!) will widen further.
Skills of average Israeli worker (PIAAC marks) are below the OECD average and will decline further, because adults' skills are determined mostly by their educational achievements – and those will decline. Additional reason of skills' decline: among those who leave Israel, the ratio of skilled and educated people is higher than their ratio in general population.