jcash17:
I'm just a parent and new to this too - but I a've been spending quite a bit of time trying to get my head around secondary report cards and the upcoming changes to GCSE scoring - moving from letter grades to a 1 - 9 scale.
I agree with Takeallday and TeenandTween - I think the first issue is to work out if the school is using similar numbering/ lettering but the meaning is different/ has changed.
You say your son went up to Year 7 as 4a in English/ Maths and if I'm understanding this correctly, he's now Year 8 and has dropped 2 levels (not clear if you mean whole levels or sub-levels) since Y7.
As I said, the GCSE scoring is going over to a 1 - 9 system: www.gov.uk/government/uploads/system/uploads/attachment_data/file/377768/2014-09-12-grading-the-new-gcses-in.pdf -
So in the new numbering system for GCSEs Level 4 = GRADE C at GCSE in old money.
I posted earlier on this about KS3/KS4 flight paths (the examples were using the old NC Level system - i.e. your primary 4A = old GCSE F+. Link to blog about KS3/4 flight paths here: leadinglearner.me/2013/10/02/targets-learning-gaps-and-flight-paths/ - and just looking at what a C at GCSE would look like in old levels - that would have your DS working at around 5C/5B territory in Year 8. I suppose in theory they should be working at old money NC Level 6c ish by end of Y8 if making good progress (so improving by 2 sub-levels each year) - entry 4a - finishing Y7 at 5b - finishing Year 8 at 6c - so there has been something of a stall - but the school may also be taking into account the changes of content (higher standards) of new GCSE/ etc...
Of course the other question is whether his targets were based on those primary school KS2 SATs 4As or not? Sometimes the in-school testing on moving up day/ first weeks of school is so much radically less than SATs performances that schools alter the targets accordingly.
But just looking at the 'flightpath' for GOOD performance - if you come in from KS2 as 4A - by the end of Y11 at GCSE on GOOD Performance [= 2 sub-levels improvement a year on old NC Level system] that results in a GCSE B- on old system - which kind of looks like low Level 5 on the new OFQUAL 1-9 GCSE scoring system.
So in that light at Y8 to be performing at Level 4 is well on target and potentially exceeding target. What did the school say about how he was working against targets? Was he on target? Exceeding target?
But as the others have suggested you should talk to the school about what system of progress measures they're using and what it means for predicted GCSE outcomes (flight path) end KS4.
I think the general point to raise is that the school have not provided parents with any explanatory notes to interpret the report card and determine how their child is doing against expected targets nationally for that age group.
HTH