How can we narrow the holes in the sieve?

Submitted by Neil Raymond on

BIO 201 is considered a ‘sieve’ class, in that it often weeds out the students who are not ready to advance to more difficult classes, and it is not uncommon for 40-50% of the class to fail, making the holes in the sieve rather large.

High school biology is the only prerequisite to enroll in BIO201 and it seems that students who have taken a BIO 156/181 prior to 201 have performed better.  To evaluate this observation, an informal survey was given to students to gather information about their previous biology experience.  

203 responses were obtained. The passing rate was 120/203 or 59%. 68 reported only high school biology and of these, 39 (58%) failed, well above the 41% course average. 44 (33%) of the remaining 135 students who reported a previous college science class failed.  

Students who have taken a prior college biology class succeeded at a higher rate than those with only a high school biology background suggesting that students benefit substantially from a 156 or 181 class.  Integrating a cell biology review into Canvas for all 201 students to complete should improve student success.

Completed Full Cycle
Course Number
BIO 201
Average: 4.7 (3 votes)


Olga Tsoudis Fri, 01/19/2018 - 10:49pm

Neil, Thank you for sharing your survey results and how you will improve on student learning. You created a good solution by including a review in Canvas for the students in order to be successful. 

Kelly Loucy Mon, 01/22/2018 - 10:05am

I appreciate that you are looking at implementing a review in Canvas for the students to address this need. I look forward to a future CATS reporting on the implementation and its impact! :)

Catherine Cochran Mon, 01/22/2018 - 11:42am

Hi Neil,

Thank you for sharing your results!  I would be curious what our students are learning in their high school biology classes, and why they are not doing as well as the those students who have taken BIO 156/181? 


Teri Graham Tue, 01/23/2018 - 10:21am


Thank you for sharing this experience with us through CATS.  I am curious how your department will utilize this data...will your require a 156 or 181 class before BIO 201?  Also, I feel it would be beneficial to also collect data on how the integration of the cell biology review in Canvas benefits (or not?) the 201 students.

Becky Baranowski Tue, 01/23/2018 - 12:35pm

This is powerful data that may help the BIO IC make changes to their pre-reqs.  I hope this data is shared with the BIO IC along with the West Valley Think Tank.  The local Principals of High Schools may be interested in seeing this data.

Thank you for taking time to submit this CATS.  

Heather Muns Tue, 01/23/2018 - 1:34pm

Hi Neil,

This is great data and a great CATS, but I think it needs a bit more until it fully closes the loop.  You have baseline data and you have identified an intervention (the cell biology review).  Now the intervention needs to be implemented and the post data collected.  Then you will be able to assess if the intervention helped with the problem.  I think this is important information to look at when determining pre-reqs for BIO classes.  Thanks for your submission.