Lesson Outcomes - Reworking the "Must, Should, Could"

The academy in which I'm currently training has a policy that every lesson should include (at least) two vital components - a lesson objective and lesson outcomes under the categories of must, should and could.

In brief, for those who may not be aware of this practice, the outcomes are statements that a class should be aware of during, or preferably at the start, of the lesson. In general, it is planned and expected that all students will be able to attain the "must" level, many will be able to get to the "should" statement, and a few would be able to reach what is expected in "could." A worked MFL example could be:

Learning Objective  - To describe actions that will happen in the future. Pupils:

• Must be able to indicate actions they will do in the future using the "aller + infinitive" model
• Should be able to indicate the actions of others in the future using the "aller + infinitive" model
• Could be able to indicate actions in the future by conjugating verbs in the future tense 

My interpretation of this has always been that the progression through the stages happens sequentially, e.g. hitting the "must" first, then the "should" and then, if time and ability allows, the "could." Also, if students can hit the first outcome then they are not only achieving the lesson objective but they are then also ready to move onto the next level.

However, a talk on Gifted and Talented students made me rethink this a little more. Instead of starting students off at "must" and then waiting to see who can progress, why not start students off at different points? Lower attainers could reach for "must," and higher attainers go for the "should" and/or "could?"

I can see why this idea would be ideal for differentiating ability levels; all students would be able to pick where they start, giving them some level of autonomy and responsibility, and those who wanted a challenge wouldn't necessarily be forced to start with a topic that they may find too easy.

Nevertheless, surely this method must be used with caution. Perhaps an able student is having an off-day and wants to take the easy route; would this show progress? Would setting work of different levels overtly to the class create a rift between pupils of different attainment levels? Are we doing pupils a disservice by asking them to take on a higher-level task when we may not have enough evidence of their grasp of easier tasks?

As per usual, the answer more than likely lies in the context of the lesson. No two lessons will be the same, thus no two approaches will ever match completely. I still intend on trying my original method and this reworked method, however, just to see how they both pan out!