First Grade Enrichment Math: Secret Numbers

This week in first grade math, we worked on using clues to locate a “secret number” on a hundreds chart.  I gave the kids four clues for each number.  As they received the clues, they used dry erase markers to eliminate numbers on the chart that could not be the secret number.  For example, if the clue was “the number is odd,” then the kids crossed off all of the even numbers.  This is a bit more confusing than perhaps it sounds, because one has to be careful to be sure to mark off the inverse of the clue (if it says that the number is even, for example, then you need to mark off the odds).  Some of the kids got the idea quickly; many of them did not.  Of course, then the clues got harder (“if you add the digits, the sum is 12,” for example).  They worked hard and with great enthusiasm (for some of them, it was almost equally difficult not to shout out the number as soon as they found it).

Homework is to create a set of four clues that lead to one and only one secret number.  All of the clues should be necessary to find the number, and they should lead to only one number.  I sent home a hundreds chart to help.  Please do not cut out the clue cards — keep them as a whole sheet, turn them in and let me check them, and then we will use them in class the next time we play “Secret Number.”  I told the kids they need to practice to be sure that their clues actually lead to one (and only one) number.  It might be a good idea to make copies of the hundreds chart, in case they need to practice more than once.

This activity was “confusing, and hard, and SO FUN” according to one of the first graders. I would say this is a pretty accurate summation of how most of the kids felt.  Your child may need some help creating his/her clues and practicing to make sure they only lead to one number.

You can find the packet at this link (Secret Number), if you need another hundreds chart or more cards.

Kindergarten Enrichment Math: What’s in Between?

We began kindergarten math this week with a discussion about what it feels like to stretch our brains.  I asked the students if I am making my body stronger when I am just sitting in my chair.  They all said no and offered that I need to exercise to make my body stronger.  Yes!  For my body to gain strength, I need to push it and let it do hard things.  The same is true of our brains.  I told the kids that if the homework I give them is easy and they can do it all correctly without thinking about it, then their brains are not growing, and I am not doing my job.  My job is to give their brains challenging work so their brains can grow stronger.

One student offered that sometimes he feels angry when work is hard or he doesn’t do it correctly.  I said that’s normal, but it’s something we should notice and try to change.  Instead of feeling anger when something is difficult, we need to acknowledge “Hey, this is hard!  That’s why I feel uncomfortable!  My brain is sore just like my body is sore after I exercise a lot.”

With that said, it’s also important not to keep pushing when something is too difficult.  If we recognize that effort is causing frustration and, despite trying our best to work through it, we still feel frustrated or angry, it is time to stop and take a break.

The students informed me that last week’s homework was “easy peasy,” and it should have been. This week’s homework should prove a bit more difficult.  We’ll build up for awhile until we hit the sweet spot.

After our little chat, the students completed their second “Five Minute Challenge,” attempting to complete 100 addition problems correctly in five minutes.  Every single student beat his or her score from last week!

We then came to the meat of our lesson, which was about finding numbers that are “in between.”  I asked the students to list numbers greater than five, then numbers less than 20, then numbers greater than five but less than twenty, then only odd numbers greater than five but less than 20.  We spent awhile changing parameters and adding requirements, and the kids did a great job.

Homework is a “What’s in Between?” worksheet.  The students need to complete the 8 problems on the front, and then write two problems for me to complete on the back.  Their problems need to include both the question and the appropriate number of blanks for me to write the answer.

For example:

List even numbers that are greater than 15 but less than 29

____, ____, ____, ____, ____, ____, ____

As I told the students, there are no specific guidelines for numbers to use or number of blanks except that the students need to write the blanks themselves.  So if your child wants me to list the odd numbers that are greater than zero but less than 500,000, s/he better be prepared to make A LOT of blanks.

I’m ready to stretch my brain and do my homework!  I hope the kids are, too!

Second Grade Enrichment Math: Babylonian Numbers

Did your second grade enrichment math student forget what I looked like?  I warned them that circumstances were conspiring against us in November, but I don’t know if they were really listening.  Between field trips and holidays and illness (mine, I’m afraid), it had been weeks since we had seen each other.  We caught up yesterday and are back on track.

This week, we started class with the riddle:

What five letter word becomes shorter when you add two letters?

Most of the kids greeted the question with frustration.  Did they tell you about it at home?

We then moved on to Babylonian numbers.  Like Ancient Egyptian numbers, Babylonian numbers are additive.  Babylonian numbers do, however, have place value.  The students were thrilled!  Place value!  Something we understand!  They were overjoyed to tell me that the place to the left of the ones place must be the tens place.  They were correct!  It was glorious.

Then they couldn’t wait to let me know that the next place had to be the hundreds place.  But nope, it didn’t have to be that at all.  In the Babylonian number system, the next place is the sixties.  A base 60 number system?  Say it isn’t so!

Here is a sample of some Babylonian numbers:


Some of the kids made (with my encouragement) “cheat sheets” listing multiples of 60.  This made translating Babylonian numerals considerably easier.  We spent the remainder of class working with Babylonian numerals and translating back and forth.  Next week, we’ll move on to yet another number system.

Welcome to kindergarten enrichment math!

I met with kindergarten math groups for the first time today. To begin, I explained that they would be coming to see me once each week for enrichment math. I told the kids that the math they do with me is supposed to be hard, and that if they don’t get it right away, that’s okay.

We then took our first Five Minute Challenge — trying to correctly complete 100 addition problems in five minutes. No one completed all 100, nor did I expect them to, but several students came close. We noted the starting scores and the kids will try to beat their scores in the coming weeks.

We then spent some time talking about even and odd numbers. We talked about how even numbers end in 0, 2, 4, 6, or 8, and odd numbers end in 1, 3, 5, 7 or 9. I told the kids that even numbers have best friends and can be divided into pairs so that everyone has a “BFF.” Odd numbers don’t all have best friends and there is always one left without a BFF. Or, as a kindergarten student explained, there’s always “an odd man out.”

Homework this week is an even and odd packet. Homework is always due one week after it is assigned. Your child can give the homework to his or her classroom teacher and it will find its way to me.

Just a blog note — if you’ve signed up to receive blog posts in your email inbox, all posts will come to you, not just the ones for the group or groups that include your child.  I used to maintain separate blogs for each group, but that became unmanageable.  Apologies if these emails bother you!

First Grade Enrichment Math: The Perplexor Pack

This week in first grade math, I introduced the students to math logic problems called Perplexors.  We worked on two Perplexors together in class, and the students worked on one or two more on their own (or in pairs).

I sent a packet of Perplexors home for homework.  The students only need to complete two Perplexors (the two we worked on together in class don’t count, but the ones they worked on independently or in pairs do).

If the students choose, I have also challenged them to complete the entire packet correctly and join the Perplexor Pack, an exclusive club only for those who have completed the first 10 Perplexors.   There is no deadline to join the Pack.  As soon as a student turns in his or her first Packet, I will hand over the second Packet, check answers and (if they’re all correct), extend membership in the Pack and teach the secret handshake.

I can’t wait to welcome new members to the Pack!

First Grade Enrichment Reading: Crime Lab Day Two

This week in First Grade Reading, we performed another series of Crime Lab tests designed to get us closer to discovering the culprit in our Pilfered Hippopotamus Mystery.

The first station required testing the white powder found on Danny.  At the station there was a cup of mystery white powder.  Was it powder used to make cookies, or powder used to make pie?  The kids used an eyedropper to add Iodine to the powder.  The station directions informed them that if the powder turned bright yellow, it was cookie powder.  If the powder turned purple or black, it was pie powder.  Who looked guilty based on the result of the test — who brought cookies and who brought pie?


Next, the students tested the melted ice cubes to determine if they contained a mystery substance.  The station directions informed them that if they dipped pH paper in the melted ice cubes and the paper stayed yellow, the ice cubes were simply water.  If the pH paper turned green, the ice cubes contained a mystery substance.


At the next station, we examined three cups.  One contained salt crystals, one contained sugar crystals, and one contained the “mystery crystals” found on Danny at the scene of the crime.


The kids looked closely at all of the crystals and tried to determine if the mystery crystals best matched the salt crystals (which were chunky) or the sugar crystals (which were smooth and shiny).


At the far corner of the room, we had the Mystery Stain station.  A paper towel with a mysterious brown stain was found at the scene.  Some of the club members had brought brown markers to the club meeting, and one had brought brown dye.  Was the stain made with marker or dye?  The kids took a strip of the paper towel and dipped the bottom of the paper in water.  The water then spread up the paper towel and through the stain.  If the stain stayed brown (just a lighter brown), the kids knew it had been made by a marker.  If the stain separated into component colors red and green, the kids new it had been made by brown dye mixed from red and green.  The kids recorded their results on their data sheets.


We then sat down to take a long look at our Data Sheets and Clue Boards.  Who looked guilty based on the tests we had performed?  What did we think happened based on the evidence we had found?


I sent the Data Sheets and Clue Boards home so that the kids could use them to complete their homework assignment — writing a paragraph or two that explains their theory of what happened and their best guess as to who took Danny.

Throughout this unit, I have been impressed by the kids’ attention to detail and their ability to make appropriate inferences.  There are a lot of pieces to tie together here, and they have shown great facility at taking information obtained in one way and applying it somewhere else.  Most of them have been careful not to jump to conclusions, and to modify their theories when the evidence contradicts them.  If I needed a group of detectives, I would hire them for sure!  If I needed a group of first graders who could pay attention to a text, make inferences about it, and connect it to other texts and situations, well, I’d hire them for that, too!