I have found for me that I learn best with a continuos effort of learn, repeat and review over a broad number of subjects instead of the learn a, then b, then c.
When I practice golf, I do not learn putting, then irons, then driving. I try all three, repeat all three, then review all three. In basketball, I do not learn dribbling, then learn shooting, then learn passing. I try to improve all three.
I believe that having the children learn english, then math, then science, then foreign language would be a mistake. I believe that throw it all at them, repeat it, push forward, go back and review, then throw it at them again, repeat, push , go back and review, etc. is the proper way to go.
That does mean learning a little spanish, chinese, or fill in the blank with subject of your choice, well before english is mastered.
I suspect, you would normally agree with this, but the mexican invasion has made you so mad that you reflexively scratch spanish off the list.
Well, you can try to bait me, but it won't work. The fact that small children are being taught Spanish as a second language BEFORE they can even read, spell, or write English is simply not right. Spanish used to be an elective- now it is being forced on public school students.