Is Pre-Algebra on KhanAcademy good enough for Algebra?

Question

Now, I learnt maths a long time ago, but I want to learn it again (kinda self-teach), mainly for computer science. I know quite a lot of arithmetic and basic geometry. I understand about exponents and logarithms. However, I would love to learn more algebra and equations.

I want to learn more about Algebra, even if it involves starting again. I've checked out KhanAcademy's Pre-Algebra and Algebra course. My question is

With my knowledge, would the Pre-Algebra tutorial help me understand most about what is taught in the Algebra tutorial?
How long is an estimate for me to learn?
Should I start with early maths before touching it? I do know maths.

I may also want to learn Linear Algebra. I might even use the lectures done by Gilbert Strang from MIT Courseware, which I've found as a recommendation on several sites. It looks quite interesting.

Thank you.

This seems like more of a question for the people that run Khan Academy. — Matthew Leingang, Jun 07 '18 at 13:16
@MatthewLeingang That might be true but Khan Academy is a really large site. I doubt that there is nobody here who knows what's it about. — Steve Woods, Jun 07 '18 at 13:19
@MichaelBurr I hope you're not trying to get this upheld...... Math Educators SE looks very inactive. I think it would be best to use the comments to help me instead. — Steve Woods, Jun 07 '18 at 13:22
Instead of asking on here, why don’t you just try it and see if you get enough preparation? If you don’t, try something else or ask on here for more resources. — Michael Burr, Jun 07 '18 at 13:59

score 0 · Accepted Answer · answered Jun 07 '18 at 13:44

If you're asking whether Khan Pre-algebra is good enough preparation for Khan Algebra, the the answer is "yes."

If you're asking whether Khan Pre-algebra counts as "knowing algebra", then the answer is "no."

My opinion about pre-algebra is that it should disappear from the face of the planet. It's been a huge mistake over the last few decades to try to teach calculus and algebra in earlier and earlier grades. Children's brains develop at well-known rates. We ignore this science and try to teach Calculus to 10th graders (and when we can't quite do it, we invent "pre-calculus" which is just algebra stripped of anything that isn't directly applied in calculus). And, worse, we try to teach algebra to 6th graders and when we fail we invent "pre-algebra" which pushes necessary things out of the curriculum for the sake of doing pointless acrobatic that are vaguely similar to stuff that's done later in real algebra.

Better to wait a couple years and then just teach the student algebra, now that his brain is developed enough to handle it easily.

Notice that there's nothing called "pre-piano".

The purpose of this rant is to say that for an adult, I firmly believe that "pre-algebra" is a waste of time. Pre-algebra was invented so that kids who are too young to grasp algebra could still play with algebra-like concepts. My advice in the end is that you just do the Khan Algebra.

Thank you for that advice. It's been quite an eye opener. Can you say what kind of ages for kids this is? 10 or 8? To be quite honest, I feel like I should learn it. After all, I will be achieving my goal of learning maths. — Steve Woods, Jun 07 '18 at 21:09
Our brains change at puberty. Before, we're just sponges soaking up data. We can really do logic and relate one thing to another. After, we suddenly have this new power to abstract and infer. Pre-algebra is for pre-puberty. I find so many of the pre-algebra exercises to be pointless and artificial. The current system forces the student to learn everything twice. Once in a pointless, artificial context and then once for real. — B. Goddard, Jun 07 '18 at 21:20

Is Pre-Algebra on KhanAcademy good enough for Algebra?

1 Answers1