Kiasu Friend:Hi there. Those are very good questions, and answering them is tricky. But I will try.(1) Do the students joining in Year 3 or Year 5 suffer at least a slight disadvantage when compared to those joining ACS(I) IP program in Year 1 itself?
(2) If they do not suffer any disadvantage, then what is the benefit in joining in Year-1 of IP program at ACS(I)? In other words, do Year-1 and 2 of the IP program at ACS (I) have any relevance to IB curriculum or these first two years of the IP program are just like Sec-1 and Sec-2 elsewhere?
In summary my question is: \"ACS(I) rightly claims that theirs is a 6-year IP program leading to IBDP. But in what specific ways the Year-1 and Year-2 contribute in preparing the students for the eventual IBDP if one can join in Year-3 or Year-5 at their own convenience?\"

1. In theory, the students joining later should have be at a disadvantage. However, most of those joining later are scholars (Year 3 entry) or selected by having very good O-level or DSA scores (Year 5 entry). Some have pointed out that late entry at Year 5 is mostly female, and yes, female students have a high average performance level.
2. The data therefore show that on average there is no disadvantage to late joiners. But whether this is due to the programme not really differentiating or whether this is due to the high quality of the late joiners has not been established yet. In most IP schools, research shows that late joiners tend to do better βΒ however, the bar to entry is also set much higher for late entry.
3. The main advantage to joining early seems to be that a student joining early will get into the flow earlier. The ACS(I) IP was originally crafted to develop skill sets that were necessary for the IB Diploma Programme. But not having those skill sets at a high level is obviously not an obstacle to doing well, if the student is highly motivated.
My personal (I stress 'personal') opinion is that the ACS(I) IP's original specifications would have been sufficiently rigorous to create a barrier that would have resulted in early entry being an outstanding advantage. The specifications have been reduced, so it is now no longer such a barrier.
I hope that answers your questions. There's an article I linked to in a post responding to tiger262 above that may be useful (especially towards the end). Cheers!