RAFT Activity Kit: Static Merry-go-Round

Monday, April 7, 2014

Forces and Motion - RAFT Retractor Car

As part of the forces and motion unit my students had the opportunity to play around with the RAFT Retractor Car Activity Kit. The modified activity [available at https://docs.google.com/document/d/17grd41wMyBj7kjTaZgBZk7x-trCcrDeQxNyx1LWYRhc/pub] involved the students building the vehicle [as specified by the project page] then deciding what they wanted to test. Students had several options:
  • how will the car perform over various surface types?
  • how might the speed or distance be impacted if the car has to travel up an incline?
  • how would increasing the mass on the car impact the speed or distance the car travels?
  • how could the design be adjusted to make the car go further or faster?
As usual, only one person selected to try this activity, at least until the rest of the students saw the car cruise across the classroom floor. Thank goodness for those students who are ‘early adopters’ and willing to try something unknown. In the end there were several groups who performed the surface test; one group tried the incline, and two messed around with the design of the car.

The incline test was based on a using textbooks to create the rise. Students used a ramp propped on one, two, or three textbooks. We were collectively disappointed when the vehicle did not manage any of the inclines; however that did spark discussion about traction which lead to wondering if wider wheels would help or if the car needed more power [two retractors?].

The students who tried different surface areas [classroom tile, rough asphalt, and cement] had some interesting explaining to do in their lab report’s data analysis section. The car performed so well in the classroom it would consistently run out of room before it ran out of power! The students who were strictly testing distance would get false data because the car would go further on the cement just by the fact it was longer. We decided, at some other point, we would need to test the vehicle in the cafeteria which is twice the length of our classroom.

The re-designer teams tried two different modifications. The first team felt sturdier wheels would improve the vehicles performance. They upgraded the plastic lid wheels for the higher end compact disc option. Apparently flash is not everything. The vehicle did not perform better! The students were surprised and concluded the CDs may have been too thin to get enough traction on the floor. The second team wanted a car with more power so they upgraded their vehicle to the dual engine [two retractors] model. When it came down to the classroom version of “fast & furious” the twin engine car had faster pick up but ultimately did not go any further. Sad news for the betting crowd in the stands.

This learning would never come from a textbook. Thank you RAFT for providing inexpensive ways for students to explore science concepts in a real world application. There was dialogue, thinking, exploring, testing, hypothesizing, analyzing, failure, success, and fun. It does not get any better than this!

Cynthia Lipsig, Teacher and RAFT Fellow

Sunday, April 6, 2014

RAFT and Common Core


As we approach the full implementation of Common Core and the Next Gen Science standards the classroom has become a far more busy and chaotic place.  Lots of learning with lots of mess and noise.

My curriculum is all designed around a grid system where students need to accumulate a certain number of points via various assignments and projects.


My first grid is learning the basics: like vocabulary, concepts, ideas, laws, formulas, etc.   There are even choices within each choice [ridiculous!]. Most of these assignments involve writing, reading, watching videos, or using a digital media to create a learning tool [ex flashcards, vocabulary game...]

My second grid is where the students apply what they learned via grid #1 and any offline/in class learning to USE their knowledge to create or complete something.  RAFT is indispensable for these types of activities.  For our forces and motion unit the students utilized four different RAFT kits in addition to all my weird RAFT supplies.

So picture a classroom of 22 high school students all in the middle of doing DIFFERENT projects and amongst all this creativity you have two students building some giant ramp out of plastic tubing and an absurd amount of masking tape.  No matter what my other students were working on everyone stopped “Hey, what assignment is that? Can we do that one too?” 
There seems to be some undeniable pleasure in sending an innocent marble hurling down a steep incline and through a maze of friction, hills, and spirals.  The RAFT supplies were perfect for creating the marble death traps as well as the bonus challenges like loops, or spirals.  The students think it is all fun and games but in the end they are able to explain where the laws of motion came into play, why having a high friction starting hill was not an advantage even if it was a steep one, and how a spiral or loop actually increases the marbles speed through the coaster.

Cynthia Lipsig, Teacher and RAFT Fellow

Saturday, April 5, 2014

In the Beginning

I began teaching at Mt. Hamilton Elementary in the early to mid 90’s. Mt. Hamilton School was a one room school located at Lick Observatory on Mt. Hamilton. I was the only teacher, and I had grades K-8 in one room (I did not always have a child in every grade). Lick Observatory is located some 20 or more miles east of San Jose in the Diablo Range. Being the only teacher I had to find other ways of networking and collaborating, and RAFT was one resource.

My first experience with RAFT was when you were in the other location. Was that in Sunnyvale? I remember walking in and thinking what is all this stuff, but on my out I saw a bin full of white binders that said FREE. I took some and, my relationship with RAFT was born.

Pat Graham, Teacher and RAFT Fellow