Tag Archives: log laws

Blogging Log Laws Blog

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Ah, Arrested Development, how I miss thee.

But onto some Log Laws….  When we last left our intrepid reporter, I had just introduced logs and was trying to figure out a way to start log laws. So I did what any self-respecting teacher would do and stole Kate’s idea.  But I was worried about my kids being able to make the leap to filling in the blanks, so I turned it into a match game:

log match game

File here (with the typos fixed.  This is why you don’t watch Gilmores while making a worksheet.  I can’t focus when there are 1,000 yellow daisies involved.)

The first row was a nice refresher after our snow day and then I gave them 2 – 3 minutes to work on each box, then we discussed the results and the rule.

Because it was a shortened day after a snow day, I had 3 central office people do a pop-in observation.  Of course they left right before we started discussing the addition/multiplication rule box when a student said, “Ms Craig, I think I found a shortcut…can’t we just multiply the arguments?” (ok, to be honest, he said “big numbers” instead of “arguments” but who can blame him?).

Also it’s fun to watch them all choose option A in the last box. Then tell them to go back and actually find the values and listen to the sound of erasing and/or “I TOLD YOU SO!”s.

In 30 minutes (minus bellringer/homework time), we got through #4 or 5 on the bottom practice.  Based on the one class in which we did finish,I think I need to go back to Kate’s and make 6-9 more scaffolded before jumping into pure craziness.

The next day was a full day and we used our laws to simplify/expand and solve equations:

log laws 2

File here.

See how I left that middle box blank?  I decided on a whim to try teaching logs on both sides the same way I taught log equations–logs ask “what power of ___ gives you ___?”  We did some preliminary work about inverses and b^(log x) [with the same base] = x then jumped into the problems. It took a little bit for them to get used to it, but I think it may just end up working.  And maybe stop them from just randomly crossing out any log they see anywhere in time.

Stay tuned for more log blogging with common logs, natural logs, and the debate over perhaps abandoning one of my favorite lessons ever.

Category: Alg II, Precal | Tags: ,