Estimating the mean from a grouped frequency table

Download the resource here

Starts with a little task on finding the midpoint. I often find this trips students up more than you would think.

Moves onto some example problem pairs and then a very (overly?) structured worksheet.

I don’t know how I feel about this level of scaffold. At least it reduces.

Then some questions that I wrote that I really like.

And then… that’s it. This filled the lesson nicely and I really didn’t feel like I needed much else.

Maybe I could have done a section where the mean is given but there is a hidden frequency, but I didn’t want to be overly prescriptive.

Rearranging equations / Changing the subject

Download : Rearranging equations [No factorisation]

Download : Rearranging equations [With factorisation]

I never know what to call this topic.

I’ve broken it down into two PowerPoints and I have run it for my year 9s over 3/4 lessons. The first PowerPoint is the better one.

There’s a focus on what it means for something to BE the subject. When I used these slides this week, these questions generated the best discussion and revealed some misconceptions I didn’t really think would be there. A significant number of the class thought 2a was fine as the subject of an equation.

Not to blow my own trumpet. but I think the questions where students have to identify if the first step was good or not was also a great conversation driver. I love this idea of just looking at the first step.

The second PowerPoint is much more boring. It’s a few example problem pairs and a few questions looking at more difficult rearrangements, where you need to factorise.

I’m sure you could jazz this up a little bit, but I really think this is challenging enough for students, and needs to be given detailed, close attention.

As always, review these on TES if you liked them or used them. Follow me on Twitter etc. All that stuff does make a difference, as sad as that is.